storage: Remove duplicitous refreshVol in Sheepdog buildVol

As of commit id '155ca616' a 'refreshVol' is called after a buildVol
succeeds in storageVolCreateXML, thus a volStorageBackendSheepdogRefreshVolInfo
call in virStorageBackendSheepdogBuildVol is no longer necessary.

Additionally, the 'conn' parameter becomes unused.
Signed-off-by: NJohn Ferlan <jferlan@redhat.com>

src/storage/storage_backend_sheepdog.c

@@ -257,7 +257,7 @@ virStorageBackendSheepdogCreateVol(virConnectPtr conn ATTRIBUTE_UNUSED,
 
 
 static int
-virStorageBackendSheepdogBuildVol(virConnectPtr conn,
+virStorageBackendSheepdogBuildVol(virConnectPtr conn ATTRIBUTE_UNUSED,
                                   virStoragePoolObjPtr pool,
                                   virStorageVolDefPtr vol,
                                   unsigned int flags)
@@ -279,9 +279,6 @@ virStorageBackendSheepdogBuildVol(virConnectPtr conn,
     if (virCommandRun(cmd, NULL) < 0)
         goto cleanup;
 
-    if (virStorageBackendSheepdogRefreshVol(conn, pool, vol) < 0)
-        goto cleanup;
-
     ret = 0;
  cleanup:
     virCommandFree(cmd);