media/ffmpeg: only show VERSIONS notice on change
media/ffmpeg: only show VERSIONS notice on change

Check if the VERSIONS file actually changed before printing the related
message.

Also print the path to the VERSIONS file to give some more context.

BUG=None
TEST=media/ffmpeg/bindgen.sh

Change-Id: I6e7cd2ace37ca99ed744a307675272a2e3c205f6
Reviewed-on: https://chromium-review.googlesource.com/c/crosvm/crosvm/+/3893752
Reviewed-by: Alexandre Courbot <301cd6a3ea50a894b4b51e385c5eb12b9a4ffc0c@chromium.org>
Commit-Queue: Daniel Verkamp <72bc170b46ec491f7bdd4359a1c0bfed274de40c@chromium.org>

google/crosvm,google/crosvm,google/crosvm,google/crosvm