Use $DISTRO_NAME instead of local lsb_release

The $DISTRO_NAME var is now set in all of the OS elements
in environment.d.  This patch removes the call to
lsb_release and instead uses the $DISTRO_NAME variable.

Change-Id: I7088eb88b6a3611fef5a21a6b62975876549465f
Merge "Use $DISTRO_NAME instead of local lsb_release"