remove spurious +x bits

These files are not directly executable, so drop the +x bits.

Change-Id: Iaf19a03a497686cc21103e7ddf08073173440dd1
Reviewed-on: https://gerrit-review.googlesource.com/c/git-repo/+/254076
Tested-by: Mike Frysinger <vapier@google.com>
Reviewed-by: David Pursehouse <dpursehouse@collab.net>