test_build_root: drop libcros checks

Nothing in the tree needs libcros anymore, so as a precursor to removing
that package, drop the root check on its version info.

TEST=`cbuildbot arm-generic-full` works
TEST=`cbuildbot x86-generic-full` works

Change-Id: I03668c6dbb4cb79dbadb0c98e3c05dca01a8045d
Reviewed-on: https://gerrit.chromium.org/gerrit/18247
Reviewed-by: Chris Masone <cmasone@chromium.org>
Commit-Ready: Mike Frysinger <vapier@chromium.org>
Tested-by: Mike Frysinger <vapier@chromium.org>
1 file changed