qom: Fix memory leak in function container_get

Valgrind reported this memory leak which occured very often.

Test scenario:

qemu-system-i386 (no arguments), only BIOS started, terminate with
monitor command (quit).

Signed-off-by: Stefan Weil <sw@weilnetz.de>
Reviewed-by: Andreas Färber <afaerber@suse.de>

qom/container.c

@@ -43,6 +43,8 @@ Object *container_get(Object *root, const char *path)
         }
     }
 
+    g_strfreev(parts);
+
     return obj;
 }