MDEV-7780 - Support for faking server version

Embedded now supports "--version=<version>", while "--version" is still silently
ignored. Also only run protocol check in non-embedded mode.

Author: svoj

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

@@ -1,5 +1,6 @@
 SELECT @@version;
 perl;
-  $cnt= grep /my_favorite_version/, `$ENV{MYSQL} -e status`;
+  $cnt= $ENV{MYSQL_TEST} =~ /mysqltest_embedded / ? 1 :
+        grep /my_favorite_version/, `$ENV{MYSQL} -e status`;
   print "$cnt\n";
 EOF

sql/mysqld.cc

@@ -8946,20 +8946,20 @@ mysqld_get_one_option(int optid, const struct my_option *opt, char *argument)
     binlog_format_used= true;
     break;
 #include <sslopt-case.h>
-#ifndef EMBEDDED_LIBRARY
   case 'V':
     if (argument)
     {
       strmake(server_version, argument, sizeof(server_version) - 1);
       set_sys_var_value_origin(&server_version_ptr, sys_var::CONFIG);
     }
+#ifndef EMBEDDED_LIBRARY
     else
     {
       print_version();
       opt_abort= 1;                    // Abort after parsing all options
     }
-    break;
 #endif /*EMBEDDED_LIBRARY*/
+    break;
   case 'W':
     if (!argument)
       global_system_variables.log_warnings++;