scripts: Switch to more portable Perl shebang

The default NetBSD package manager is pkgsrc and it installs Perl
along other third party programs under custom and configurable prefix.
The default prefix for binary prebuilt packages is /usr/pkg, and the
Perl executable lands in /usr/pkg/bin/perl.

This change switches "/usr/bin/perl" to "/usr/bin/env perl" as it's
the most portable solution that should work for almost everybody.
Perl's executable is detected automatically.

This change switches -w option passed to the executable with more
modern "use warnings;" approach. There is no functional change to the
default behavior.

While there, drop "require 5" from scripts/namespace.pl (Perl from 1994?).
Signed-off-by: Kamil Rytarowski <n54@gmx.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

scripts/bootgraph.pl

-#!/usr/bin/perl
+#!/usr/bin/env perl
 
 # Copyright 2008, Intel Corporation
 #

scripts/checkincludes.pl

-#!/usr/bin/perl
+#!/usr/bin/env perl
 #
 # checkincludes: find/remove files included more than once
 #

scripts/checkpatch.pl

-#!/usr/bin/perl -w
+#!/usr/bin/env perl
 # (c) 2001, Dave Jones. (the file handling bit)
 # (c) 2005, Joel Schopp <jschopp@austin.ibm.com> (the ugly bit)
 # (c) 2007,2008, Andy Whitcroft <apw@uk.ibm.com> (new conditions, test suite)
@@ -6,6 +6,7 @@
 # Licensed under the terms of the GNU GPL License version 2
 
 use strict;
+use warnings;
 use POSIX;
 use File::Basename;
 use Cwd 'abs_path';

scripts/checkstack.pl

-#!/usr/bin/perl
+#!/usr/bin/env perl
 
 #	Check the stack usage of functions
 #

scripts/checkversion.pl

-#! /usr/bin/perl
+#! /usr/bin/env perl
 #
 # checkversion find uses of LINUX_VERSION_CODE or KERNEL_VERSION
 # without including <linux/version.h>, or cases of

scripts/cleanfile

-#!/usr/bin/perl -w
+#!/usr/bin/env perl
 #
 # Clean a text file -- or directory of text files -- of stealth whitespace.
 # WARNING: this can be a highly destructive operation.  Use with caution.
 #
 
+use warnings;
 use bytes;
 use File::Basename;
 

scripts/cleanpatch

-#!/usr/bin/perl -w
+#!/usr/bin/env perl
 #
 # Clean a patch file -- or directory of patch files -- of stealth whitespace.
 # WARNING: this can be a highly destructive operation.  Use with caution.
 #
 
+use warnings;
 use bytes;
 use File::Basename;
 

scripts/dtc/dt_to_config

-#!/usr/bin/perl
+#!/usr/bin/env perl
 
 # Copyright 2016 by Frank Rowand
 # Copyright 2016 by Gaurav Minocha

scripts/export_report.pl

-#!/usr/bin/perl -w
+#!/usr/bin/env perl
 #
 # (C) Copyright IBM Corporation 2006.
 #	Released under GPL v2.
@@ -7,6 +7,7 @@
 # Usage: export_report.pl -k Module.symvers [-o report_file ] -f *.mod.c
 #
 
+use warnings;
 use Getopt::Std;
 use strict;
 

scripts/extract-module-sig.pl

-#!/usr/bin/perl -w
+#!/usr/bin/env perl
 #
 # extract-mod-sig <part> <module-file>
 #
@@ -12,6 +12,7 @@
 #  -k: Just the key ID
 #  -s: Just the crypto signature or PKCS#7 message
 #
+use warnings;
 use strict;
 
 die "Format: $0 -[0adnks] module-file >out\n"

scripts/extract-sys-certs.pl

-#!/usr/bin/perl -w
+#!/usr/bin/env perl
 #
+use warnings;
 use strict;
 use Math::BigInt;
 use Fcntl "SEEK_SET";

scripts/extract_xc3028.pl

-#!/usr/bin/perl
+#!/usr/bin/env perl
 
 # Copyright (c) Mauro Carvalho Chehab <mchehab@infradead.org>
 # Released under GPLv2

scripts/get_dvb_firmware

-#!/usr/bin/perl
+#!/usr/bin/env perl
 #     DVB firmware extractor
 #
 #     (c) 2004 Andrew de Quincey

scripts/get_maintainer.pl

-#!/usr/bin/perl -w
+#!/usr/bin/env perl
 # (c) 2007, Joe Perches <joe@perches.com>
 #           created from checkpatch.pl
 #
@@ -10,6 +10,7 @@
 #
 # Licensed under the terms of the GNU GPL License version 2
 
+use warnings;
 use strict;
 
 my $P = $0;

scripts/headerdep.pl

-#! /usr/bin/perl
+#! /usr/bin/env perl
 #
 # Detect cycles in the header file dependency graph
 # Vegard Nossum <vegardno@ifi.uio.no>

scripts/headers_check.pl

-#!/usr/bin/perl -w
+#!/usr/bin/env perl
 #
 # headers_check.pl execute a number of trivial consistency checks
 #
@@ -18,6 +18,7 @@
 #
 # 3) Check for leaked CONFIG_ symbols
 
+use warnings;
 use strict;
 use File::Basename;
 

scripts/kconfig/streamline_config.pl

-#!/usr/bin/perl -w
+#!/usr/bin/env perl
 #
 # Copyright 2005-2009 - Steven Rostedt
 # Licensed under the terms of the GNU GPL License version 2
@@ -42,6 +42,7 @@
 #    mv config_strip .config
 #    make oldconfig
 #
+use warnings;
 use strict;
 use Getopt::Long;
 

scripts/kernel-doc

-#!/usr/bin/perl -w
+#!/usr/bin/env perl
 
+use warnings;
 use strict;
 
 ## Copyright (c) 1998 Michael Zucchi, All Rights Reserved        ##

scripts/kernel-doc-xml-ref

-#!/usr/bin/perl -w
+#!/usr/bin/env perl
 
+use warnings;
 use strict;
 
 ## Copyright (C) 2015  Intel Corporation                         ##

scripts/markup_oops.pl

-#!/usr/bin/perl
+#!/usr/bin/env perl
 
 use File::Basename;
 use Math::BigInt;

scripts/namespace.pl

-#!/usr/bin/perl -w
+#!/usr/bin/env perl
 #
 #	namespace.pl.  Mon Aug 30 2004
 #
@@ -62,7 +62,7 @@
 #	  result.
 #
 
-require 5;	# at least perl 5
+use warnings;
 use strict;
 use File::Find;
 

scripts/profile2linkerlist.pl

-#!/usr/bin/perl
+#!/usr/bin/env perl
 
 #
 # Takes a (sorted) output of readprofile and turns it into a list suitable for

scripts/recordmcount.pl

-#!/usr/bin/perl -w
+#!/usr/bin/env perl
 # (c) 2008, Steven Rostedt <srostedt@redhat.com>
 # Licensed under the terms of the GNU GPL License version 2
 #
@@ -106,6 +106,7 @@
 # 9) Move the result back to the original object.
 #
 
+use warnings;
 use strict;
 
 my $P = $0;

scripts/stackdelta

-#!/usr/bin/perl
+#!/usr/bin/env perl
 
 # Read two files produced by the stackusage script, and show the
 # delta between them.