Bump gloo (#16638)

Summary:
This bump includes:
* Memory leak fix where the Gloo transport would hold on to auxiliary
  structures for send/recv pairs after they finished.
* Fix write-after-free from Gloo thread during stack unwinding on error.
* Removal of the PATENTS file.

Fixes #16144.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/16638

Differential Revision: D13937950

Pulled By: pietern

fbshipit-source-id: 3cfecaf13ee0f214c06681386557a4b1c3e1d6b9

diff --git a/third_party/gloo b/third_party/gloo
index cdeb59d..670b4d4 160000 (submodule)
--- a/third_party/gloo
+++ b/third_party/gloo
@@ -1 +1 @@
-Subproject commit cdeb59d5c82e5401445b4c051bb396f6738d4a19
+Subproject commit 670b4d4aa46886cc66874e2a4dc846f5cfc2a285