MDEV-16172 Remove InnoDB 5.7 version number from MariaDB 10.3 onwards

Because the InnoDB implementation in MariaDB has diverged from MySQL,
it is not meaningful to report a MySQL version number for InnoDB
any more. Some examples include:

MariaDB 10.1 (which is based on MySQL 5.6) included encryption and
variable-size page compression before MySQL 5.7 introduced them.
MariaDB 10.2 (based on MySQL 5.7) introduced persistent AUTO_INCREMENT
(MDEV-6076) in a GA release before MySQL 8.0.
MariaDB 10.3 (based on MySQL 5.7) introduced instant ADD COLUMN
(MDEV-11369) before MySQL.

All of these features use a different implementation and file format.
Also, some features were never merged from MySQL 5.7, and thus MariaDB
is not affected by related bugs. Examples include CREATE TABLESPACE
and the reimplementation of the partitioning engine.

mysql-test/suite/sys_vars/r/sysvars_innodb.result

@@ -2403,7 +2403,7 @@ READ_ONLY	YES
 COMMAND_LINE_ARGUMENT	NONE
 VARIABLE_NAME	INNODB_VERSION
 SESSION_VALUE	NULL
-GLOBAL_VALUE	5.7.21
+GLOBAL_VALUE	10.3.7
 GLOBAL_VALUE_ORIGIN	COMPILE-TIME
 DEFAULT_VALUE	NULL
 VARIABLE_SCOPE	GLOBAL

mysql-test/suite/sys_vars/t/innodb_stats_include_delete_marked_basic.test

@@ -18,11 +18,6 @@
 
 --source include/have_innodb.inc
 
-if (`select plugin_auth_version <= "5.7.17" from information_schema.plugins where plugin_name='innodb'`)
-{
-  --skip Not present before MySQL 5.7.17 or 5.6.35
-}
-
 ####################################################################
 #   Display default value                                          #
 ####################################################################

mysql-test/suite/sys_vars/t/sysvars_innodb.test

@@ -3,11 +3,6 @@
 --source include/not_valgrind.inc
 --source include/word_size.inc
 
-if (`select plugin_auth_version <= "5.6.34-79.1" from information_schema.plugins where plugin_name='innodb'`)
-{
-  --skip Not fixed in XtraDB as of 10.1.21-MariaDB or earlier
-}
-
 --vertical_results
 --replace_regex /^\/\S+/PATH/ /\.\//PATH/
 select * from information_schema.system_variables

storage/innobase/include/univ.i

@@ -50,16 +50,14 @@ calculated in make_version_string() in sql/sql_show.cc like this:
 because the version is shown with only one dot, we skip the last
 component, i.e. we show M.N.P as M.N */
 #define INNODB_VERSION_SHORT	\
-	(INNODB_VERSION_MAJOR << 8 | INNODB_VERSION_MINOR)
+	(MYSQL_VERSION_MAJOR << 8 | MYSQL_VERSION_MINOR)
 
 #define INNODB_VERSION_STR			\
-	IB_TO_STR(INNODB_VERSION_MAJOR) "."	\
-	IB_TO_STR(INNODB_VERSION_MINOR) "."	\
-	IB_TO_STR(INNODB_VERSION_BUGFIX)
+	IB_TO_STR(MYSQL_VERSION_MAJOR) "."	\
+	IB_TO_STR(MYSQL_VERSION_MINOR) "."	\
+	IB_TO_STR(MYSQL_VERSION_PATCH)
 
-#define REFMAN "http://dev.mysql.com/doc/refman/"	\
-	IB_TO_STR(INNODB_VERSION_MAJOR) "."		\
-	IB_TO_STR(INNODB_VERSION_MINOR) "/en/"
+#define REFMAN "http://dev.mysql.com/doc/refman/5.7/en/"
 
 /** How far ahead should we tell the service manager the timeout
 (time in seconds) */