Sync wayland packages with upstream

Upgraded dev-libs/wayland to version 1.21.0-r1 on amd64
Upgraded dev-libs/wayland-protocols to version 1.31 on amd64
Upgraded dev-util/wayland-scanner to version 1.21.0 on amd64

BUG=none
TEST=CQ

Change-Id: I9f7bc995a886efb262c0503c2e4a7c9cb25143e9
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/overlays/portage-stable/+/4288793
Reviewed-by: James Ye <jamesye@google.com>
Auto-Submit: Fergus Dall <sidereal@google.com>
Commit-Queue: Fergus Dall <sidereal@google.com>
Tested-by: Fergus Dall <sidereal@google.com>
Commit-Queue: James Ye <jamesye@google.com>
4 files changed