x11-libs: Sync ebuilds with upstream

Changes are mostly about using xorg-3 eclass methods

BUG=none
TEST=sudo emerge pacakges

Change-Id: Ida6ab0f60e991a247a3ab55aaf929f7319a00462
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/overlays/portage-stable/+/2915041
Reviewed-by: David Riley <davidriley@chromium.org>
Tested-by: Fergus Dall <sidereal@google.com>
Commit-Queue: Fergus Dall <sidereal@google.com>
11 files changed