virStorageSourceClear: Unref @vhostuser

The @vhostuser member of virStorageSource structure is allocated
during parsing in virDomainDiskSourceVHostUserParse() but never
freed leading to a memleak. Since the member is an object it has
to be unrefed instead of g_free()-d.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>

src/conf/storage_source_conf.c

@@ -1125,6 +1125,7 @@ virStorageSourceClear(virStorageSourcePtr def)
     virStorageEncryptionFree(def->encryption);
     virStoragePRDefFree(def->pr);
     virStorageSourceNVMeDefFree(def->nvme);
+    virObjectUnref(def->vhostuser);
     virStorageSourceSeclabelsClear(def);
     virStoragePermsFree(def->perms);
     VIR_FREE(def->timestamps);