mesa: add missing null check in _mesa_NewHashTable()

Signed-off-by: Juha-Pekka Heikkila <juhapekka.heikkila@gmail.com>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>

src/mesa/main/hash.c

@@ -115,10 +115,20 @@ _mesa_NewHashTable(void)
 
    if (table) {
       table->ht = _mesa_hash_table_create(NULL, uint_key_compare);
+      if (table->ht == NULL) {
+         free(table);
+         _mesa_error_no_memory(__func__);
+         return NULL;
+      }
+
       _mesa_hash_table_set_deleted_key(table->ht, uint_key(DELETED_KEY_VALUE));
       mtx_init(&table->Mutex, mtx_plain);
       mtx_init(&table->WalkMutex, mtx_plain);
    }
+   else {
+      _mesa_error_no_memory(__func__);
+   }
+
    return table;
 }