thirdpartymirrors: pull updates from upstream

Update lists of 3rd party mirrors to latest upstream Gentoo.
This culls a lot of dead sites like old SF hosts.

BUG=chromium:1081913
TEST=CQ passes

Change-Id: Ife5f910b5b7a0289577e9344fd175c6363edd247
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/overlays/portage-stable/+/2197400
Reviewed-by: Manoj Gupta <manojgupta@chromium.org>
Reviewed-by: Alex Klein <saklein@chromium.org>
Tested-by: Mike Frysinger <vapier@chromium.org>
Commit-Queue: Mike Frysinger <vapier@chromium.org>
1 file changed