virDomainDeviceInfoParseXML: Clear whole @info on failure

Currently, if parsing of device info fails info->alias is freed.
It doesn't make much sense to leave the rest of the struct
behind.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>

src/conf/domain_conf.c

@@ -6476,7 +6476,7 @@ virDomainDeviceInfoParseXML(xmlNodePtr node,
     ret = 0;
  cleanup:
     if (ret < 0)
-        VIR_FREE(info->alias);
+        virDomainDeviceInfoClear(info);
     VIR_FREE(type);
     VIR_FREE(rombar);
     return ret;