storage: Clean up stateFile if refreshPool fails

If the virStoragePoolRefresh fails and we call stopPool, the
code neglected to clean up the state file leading to the next
libvirtd restart attempting to start the pool. For a transient
pool this could make it unexpectedly reappear.
Signed-off-by: NJohn Ferlan <jferlan@redhat.com>
ACKed-by: NMichal Privoznik <mprivozn@redhat.com>

src/storage/storage_driver.c

@@ -1171,8 +1171,13 @@ storagePoolRefresh(virStoragePoolPtr pool,
 
     virStoragePoolObjClearVols(obj);
     if (backend->refreshPool(obj) < 0) {
+        char *stateFile = virFileBuildPath(driver->stateDir, def->name, ".xml");
+
+        if (stateFile)
+            unlink(stateFile);
         if (backend->stopPool)
             backend->stopPool(obj);
+        VIR_FREE(stateFile);
 
         event = virStoragePoolEventLifecycleNew(def->name,
                                                 def->uuid,