Fix compile warning about passing NULL to non-pointer

argument of inline_mysql_mutex_init in sql_base.cc.

When initializing LOCK_dd_owns_lock_open mutex pass
correct PSI key instead of NULL value.

mysql-test/suite/perfschema/r/dml_setup_instruments.result

@@ -13,7 +13,7 @@ wait/synch/mutex/sql/LOCK_active_mi	YES	YES
 wait/synch/mutex/sql/LOCK_audit_mask	YES	YES
 wait/synch/mutex/sql/LOCK_connection_count	YES	YES
 wait/synch/mutex/sql/LOCK_crypt	YES	YES
-wait/synch/mutex/sql/LOCK_delayed_create	YES	YES
+wait/synch/mutex/sql/LOCK_dd_owns_lock_open	YES	YES
 select * from performance_schema.SETUP_INSTRUMENTS
 where name like 'Wait/Synch/Rwlock/sql/%'
   and name not in ('wait/synch/rwlock/sql/CRYPTO_dynlock_value::lock')

sql/sql_base.cc

@@ -104,9 +104,10 @@ mysql_mutex_t LOCK_dd_owns_lock_open;
 uint dd_owns_lock_open= 0;
 
 #ifdef HAVE_PSI_INTERFACE
-static PSI_mutex_key key_LOCK_open;
+static PSI_mutex_key key_LOCK_open, key_LOCK_dd_owns_lock_open;
 static PSI_mutex_info all_tdc_mutexes[]= {
-  { &key_LOCK_open, "LOCK_open", PSI_FLAG_GLOBAL }
+  { &key_LOCK_open, "LOCK_open", PSI_FLAG_GLOBAL },
+  { &key_LOCK_dd_owns_lock_open, "LOCK_dd_owns_lock_open", PSI_FLAG_GLOBAL }
 };
 
 /**
@@ -300,7 +301,8 @@ bool table_def_init(void)
   init_tdc_psi_keys();
 #endif
   mysql_mutex_init(key_LOCK_open, &LOCK_open, MY_MUTEX_INIT_FAST);
-  mysql_mutex_init(NULL, &LOCK_dd_owns_lock_open, MY_MUTEX_INIT_FAST);
+  mysql_mutex_init(key_LOCK_dd_owns_lock_open, &LOCK_dd_owns_lock_open,
+                   MY_MUTEX_INIT_FAST);
   oldest_unused_share= &end_of_unused_share;
   end_of_unused_share.prev= &oldest_unused_share;