exec: fix memory leak in find_max_supported_pagesize()

The string returned by object_property_get_str() is dynamically allocated.
Signed-off-by: NGreg Kurz <groug@kaod.org>
Message-Id: <152231458624.69730.1752893648612848392.stgit@bahia.lan>
Reviewed-by: NCornelia Huck <cohuck@redhat.com>
Reviewed-by: NThomas Huth <thuth@redhat.com>
Signed-off-by: NEduardo Habkost <ehabkost@redhat.com>

exec.c

@@ -1495,6 +1495,7 @@ static int find_max_supported_pagesize(Object *obj, void *opaque)
         mem_path = object_property_get_str(obj, "mem-path", NULL);
         if (mem_path) {
             long hpsize = qemu_mempath_getpagesize(mem_path);
+            g_free(mem_path);
             if (hpsize < *hpsize_min) {
                 *hpsize_min = hpsize;
             }