Update git submodules

* Update docs/submodules/barometer from branch 'master'
  - src: build and install collectd on centos/rhel

    Modify build and dependency scripts for centos/rhel builds.

    Change-Id: I1fafaf3392d9f22837ce4ed3fa0f84c13ead0698
    Signed-off-by: Maryam Tahhan <maryam.tahhan@intel.com>

diff --git a/docs/submodules/barometer b/docs/submodules/barometer
index 3869954..db68b7e 160000 (submodule)
--- a/docs/submodules/barometer
+++ b/docs/submodules/barometer
@@ -1 +1 @@
-Subproject commit 386995473879eb0502c502ad69d06e2d5bd9d7a9
+Subproject commit db68b7e767351f8b59db586e4035f501facf92a9