ChangeLog: drop unused files

We used to sync these to try and keep everything in sync in the tree,
but we ended up not doing that anymore, so punt them all.  This also
cleans up useless hits in codesearch.

BUG=None
TEST=CQ passes

Change-Id: I79e2244012ed385edda0b68b1665dfbabfc05eeb
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/overlays/portage-stable/+/2366113
Tested-by: Mike Frysinger <vapier@chromium.org>
Auto-Submit: Mike Frysinger <vapier@chromium.org>
Reviewed-by: Michael Mortensen <mmortensen@google.com>
48 files changed