Merge pull request #236 from alistair23/alistair/tock-bump

tock: Bump to the latest commit
diff --git a/tock b/tock
index 6260afa..c5b7a4f 160000
--- a/tock
+++ b/tock
@@ -1 +1 @@
-Subproject commit 6260afac204ae9f469abe9e2573cb51d3b124624
+Subproject commit c5b7a4f2c89a8c067f0f5786788f4037b32329fd