truncating a temporary table

TRUNCATE expects only one TABLE instance (which is used by TRUNCATE
itself) to be open. However this requirement wasn't enforced after
"MDEV-5535: Cannot reopen temporary table".

Fixed by closing unused table instances before performing TRUNCATE.

rec_offs_nth_extern_old() was introduced in
commit a4948daf
and never used.

storage/rocksdb/rdb_datadic.cc: In member function 'int myrocks::Rdb_key_def::unpack_integer(myrocks::Rdb_field_packing*, Field*, uchar*, myrocks::Rdb_string_reader*, myrocks::Rdb_string_reader*) const'
storage/rocksdb/rdb_datadic.cc:1781:1: internal compiler error: Segmentation fault
 }

on ppc64le, ubuntu bionic gcc 7.3.0 and debian stretch gcc 6.3.0

The error happens with -ftree-loop-vectorize when trying to vectorize
a particular loop (see Rdb_key_def::unpack_integer())

Compiler gets confused by __attribute__((optimize("O0")) that comes from
ha_rocksdb_proto.h. The intention of this __attribute__ was to prevent
function from being inlined (see ha_rocksdb.cc). Let's use a more
specific attribute that prevents inlining but does not confuse
loop vectorizer.

An error in "group commit with MariaDB's binlog" code: we would flush
the WAL even when the transaction did not do any writes (and so the logic
in myrocks::Rdb_transaction::commit caused it to rollback).

Reset query cache after every test case and add wait after
load infile.

to guarantee that it's destroyed when plugin deinit is called, not after

(already fixed in 10.2. bad merge?)

Use RedHat-recommended /var/lib/rpm-state/mariadb/ for restart flag.
This also fixes SUSE where /var/lib/rpm-state doesn't necessarily exist.

cover ALTER TABLE

MDEV-16792 Assertion `m_status == DA_ERROR' failed in Diagnostics_area::sql_errno or wrong result upon SHOW TABLE STATUS after adding partition under ANSI_QUOTES

if opening a table fails with a syntax error, the error shouldn't
be suppressed completely as if it didn't happen at all.

Unary minus operation for the smallest possible signed long long value
(LONLONG_MIN) is undefined in C++. Because of this, func_time.test
failed on ppc64 buildbot machines.

Fixing the code to avod using undefined operations.

This is fix is similar to "MDEV-7973 bigint fail with gcc 5.0"

MDEV-16429: Assertion `!table || (!table->read_set || bitmap_is_set(table->read_set, field_index))' fails upon attempt to update virtual column on partitioned versioned table

When using buffered sort in `UPDATE`, keyread is used. In this case,
`TABLE::update_virtual_field` should be aborted, but it actually isn't,
because it is called not with a top-level handler, but with the one that
is actually going to access the disk. Here the problemm is issued with
partitioning, so the solution is to recursively mark for keyread all the
underlying partition handlers.

* ha_partition: update keyread state for child partitions

Closes #800

Followup for 96b89090. Only link mysqld with
${INTERFACE_LIBS} using LINK_PUBLIC, everything else should be
using LINK_PRIVATE. This restores pre-96b89090 behavior.

Also fixes
MDEV-17010 Multiple definition issue on FreeBSD after 10.3.9 update

This reverts commit 87609324

RocksDB was making invalid assumption about Field_blob::make_sort_key,
and the commit 87609324 changed Field_blob::make_sort_key to match
RocksDB assumptions.

It also unintentionaly broke sys_vars.max_sort_length_func

RPM solution:

Make all server plugins to restart the server when installed.
To avoid multiple server restarts, do it only once in posttrans scriptlet.
Add support for CPACK_RPM_<component>_POST_TRANS_SCRIPT_FILE