Remove remaining InnoDB references to the TABLESPACE keyword

MySQL 5.7 allows the creation of InnoDB tables in a user-created
tablespace, but MariaDB does not. Remove the remaining references.

This is a non-functional change.

storage/innobase/handler/ha_innodb.cc

@@ -49,9 +49,6 @@ this program; if not, write to the Free Software Foundation, Inc.,
 #include <sql_class.h>
 #include <sql_show.h>
 #include <sql_table.h>
-#include <sql_tablespace.h>
-// MySQL 5.7 Header */
-// #include <sql_thd_internal_api.h>
 #include <table_cache.h>
 #include <my_check_opt.h>
 #include <my_bitmap.h>

storage/innobase/handler/handler0alter.cc

@@ -409,12 +409,10 @@ innobase_need_rebuild(
 	    == Alter_inplace_info::CHANGE_CREATE_OPTION
 	    && !(ha_alter_info->create_info->used_fields
 		 & (HA_CREATE_USED_ROW_FORMAT
-			 | HA_CREATE_USED_KEY_BLOCK_SIZE))) {
-		// JAN: TODO: MySQL 5.7
-		//		    | HA_CREATE_USED_TABLESPACE))) {
+		    | HA_CREATE_USED_KEY_BLOCK_SIZE))) {
 		/* Any other CHANGE_CREATE_OPTION than changing
-		ROW_FORMAT, KEY_BLOCK_SIZE or TABLESPACE can be done
-		without rebuilding the table. */
+		ROW_FORMAT or KEY_BLOCK_SIZE can be done without
+		rebuilding the table. */
 		return(false);
 	}