checkpatch: remove missing switch/case break test

This test doesn't work well and newer compilers are much better
at emitting this warning.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Cambda Zhu <cambda@linux.alibaba.com>
Link: http://lkml.kernel.org/r/7e25090c79f6a69d502ab8219863300790192fe2.camel@perches.comSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>

scripts/checkpatch.pl

@@ -6543,31 +6543,6 @@ sub process {
 			}
 		}
 
-# check for case / default statements not preceded by break/fallthrough/switch
-		if ($line =~ /^.\s*(?:case\s+(?:$Ident|$Constant)\s*|default):/) {
-			my $has_break = 0;
-			my $has_statement = 0;
-			my $count = 0;
-			my $prevline = $linenr;
-			while ($prevline > 1 && ($file || $count < 3) && !$has_break) {
-				$prevline--;
-				my $rline = $rawlines[$prevline - 1];
-				my $fline = $lines[$prevline - 1];
-				last if ($fline =~ /^\@\@/);
-				next if ($fline =~ /^\-/);
-				next if ($fline =~ /^.(?:\s*(?:case\s+(?:$Ident|$Constant)[\s$;]*|default):[\s$;]*)*$/);
-				$has_break = 1 if ($rline =~ /fall[\s_-]*(through|thru)/i);
-				next if ($fline =~ /^.[\s$;]*$/);
-				$has_statement = 1;
-				$count++;
-				$has_break = 1 if ($fline =~ /\bswitch\b|\b(?:break\s*;[\s$;]*$|exit\s*\(\b|return\b|goto\b|continue\b)/);
-			}
-			if (!$has_break && $has_statement) {
-				WARN("MISSING_BREAK",
-				     "Possible switch case/default not preceded by break or fallthrough comment\n" . $herecurr);
-			}
-		}
-
 # check for /* fallthrough */ like comment, prefer fallthrough;
 		my @fallthroughs = (
 			'fallthrough',