This fixes up commit d22c8cae

The previous threads locked need to be released too.

This occurs if the initialization of any of the non-first
mutex/conditition variables errors occurs.

Fix a bug of unreleased lock ctrl_mutex in the method create_worker_threads

added summary/description per package.

When transaction creates or drops temporary tables and afterward its statement
faces an error even the transactional table statement's cached ROW
format events get involved into binlog and are visible after the transaction's commit.

Fixed with proper analysis of whether the errored-out statement needs
to be rolled back in binlog.
For instance a fact of already cached CREATE or DROP for temporary
tables by previous statements alone
does not cause to retain the being errored-out statement events in the
cache.
Conversely, if the statement creates or drops a temporary table
itself it can't be rolled back - this rule remains.

In commit c091a0bc we removed
the use of the HASH_ macros for inserting into
buf_pool.page_hash, or accessing buf_page_t::hash.

However, the binary buddy allocator for block->page.zip.data would
still use the HASH_ macros. HASH_INSERT and not HASH_DELETE would reset
the next-block pointer to the null pointer. Our replacement of
HASH_DELETE() will reset the next-block pointer, and the replacement of
HASH_INSERT() assumes that the pointer is the null pointer.

buf_LRU_block_free_non_file_page(): Assert that the next-block pointer
is the null pointer.

buf_buddy_block_free(): Reset the pointer before invoking
buf_LRU_block_free_non_file_page(). Without this, the added
assertion would fail in the test encryption.innochecksum.

old ftp.pcre.org is apparently down,
www.pcre.org says to use github as the primary download location

MySQL 5.5 in commit 177d8b0c
introduced a configuration parameter innodb_force_load_corrupted
whose purpose was to allow a corrupted table to be dropped.

Given that MDEV-11412 in MariaDB 10.5.4 aims to allow any metadata
for a missing or corrupted table to be dropped, and given that
MDEV-17567 and MDEV-25506 and related tasks made DDL operations
crash-safe, the parameter no longer serves any purpose.

Because this obscure parameter was read-only (not settable by a client),
it seems that we can simply declare it with MARIADB_REMOVED_OPTION
(commit 1bc9cce7) without breaking
any upgrades.

DICT_ERR_IGNORE_INDEX: Replaces DICT_ERR_IGNORE_INDEX_ROOT and
DICT_ERR_IGNORE_CORRUPT, which were always set equally.

dict_load_indexes(): Report "No indexes found for table" in
a uniform way, and only when the DICT_ERR_IGNORE_INDEX flag is
not set.

If the clustered index is marked corrupted, and the operation
is DICT_ERR_IGNORE_DROP (we are about to drop the table), we will
load the metadata; else, we will return DB_INDEX_CORRUPT.

If SYS_INDEXES.PAGE is FIL_NULL, report an error or warning
unless we are about to drop the table.

dict_load_table_one(): Simplify the logic.

This reverts commit 5d6f3ceb.

Drop and add same key is considered rename (look ALTER_RENAME_INDEX in
fill_alter_inplace_info()). But in this case order of keys may be
changed, because mysql_prepare_alter_table() yet does not know about
rename and treats 2 operations: drop and add.

In that case we disable inplace algorithm for such engines as Memory,
MyISAM and Aria with ALTER_INDEX_ORDER flag. These engines have no
specialized check_if_supported_inplace_alter() and default
handler::check_if_supported_inplace_alter() sees an unknown flag and
returns HA_ALTER_INPLACE_NOT_SUPPORTED.

ha_innobase::check_if_supported_inplace_alter() works differently and
inplace is not disabled (with the help of modified
INNOBASE_INPLACE_IGNORE). add_drop_v_cols fork was also tweaked as it
wrongly failed with MSG_UNSUPPORTED_ALTER_ONLINE_ON_VIRTUAL_COLUMN
when it seen ALTER_INDEX_ORDER.

No-op operation must be still no-op no matter of ALTER_INDEX_ORDER
presence, so we tweek its condition as well.