Follow-up for the patch for bugs #12472/#15137 "CREATE TABLE ... SELECT ...

which explicitly or implicitly uses stored function gives 'Table not locked'
error"

Test case for these bugs crashed in --ps-protocol mode. The crash was caused
by incorrect usage of check_grant() routine from create_table_precheck()
routine. The former assumes that either number of tables to be inspected by
it is limited explicitly (i.e. is is not UINT_MAX) or table list used and
thd->lex->query_tables_own_last value correspond to each other.
create_table_precheck() was not fulfilling this condition and crash happened.
The fix simply sets number of tables to be inspected by check_grant() to 1.

sql/sql_parse.cc

@@ -7227,7 +7227,7 @@ bool create_table_precheck(THD *thd, TABLE_LIST *tables,
 			       lex->create_info.merge_list.first))
     goto err;
   if (grant_option && want_priv != CREATE_TMP_ACL &&
-      check_grant(thd, want_priv, create_table, 0, UINT_MAX, 0))
+      check_grant(thd, want_priv, create_table, 0, 1, 0))
     goto err;
 
   if (select_lex->item_list.elements)