Update git submodules

* Update trusty/user/app/sample from branch 'master'
  to 79551b1b8af53045504491f35ea5e183373579cc
  - [libc-test] Smoke test localtime
    
    Bug: 138738352
    Change-Id: I41c6fee38f63d9392813fd814bfdcc1328a5b3b4
    
diff --git a/trusty/user/app/sample b/trusty/user/app/sample
index a62e65f..79551b1 160000
--- a/trusty/user/app/sample
+++ b/trusty/user/app/sample
@@ -1 +1 @@
-Subproject commit a62e65ff52b3feb8d2d46ddece884f0943d41bb0
+Subproject commit 79551b1b8af53045504491f35ea5e183373579cc