Update git submodules

* Update docs/submodules/yardstick from branch 'master'
  - Merge "Adapt lmbench scripts for aarch64 nodes"
  - Adapt lmbench scripts for aarch64 nodes

    LMBench shell scripts were invoking x86_64 executables.
    This made them fail when executed on aarch64 nodes.
    Added architecture detection and proper command call.

    JIRA: ARMBAND-268

    Change-Id: I8c9e87158631f7f5479adc2fda9558f9f7e54406
    Signed-off-by: Alexandru Nemes <alexandru.nemes@enea.com>

diff --git a/docs/submodules/yardstick b/docs/submodules/yardstick
index 0509cf3..ec5467f 160000 (submodule)
--- a/docs/submodules/yardstick
+++ b/docs/submodules/yardstick
@@ -1 +1 @@
-Subproject commit 0509cf3e141b550653e642083907a584450a7fdf
+Subproject commit ec5467f1d2ff5fbf994018707de295fd5c02f7f9