build_packages: dump unusable nobuildretry argument

The retries argument doesn't exist for emerge. Most likely a
remnant of parallel_emerge. Dump the argument.

BUG=None
TEST=build_packages --nobuildretry fails parsing arguments

Change-Id: I1f521a453dfc2df1bfb913dd957f7d1177818528
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/crosutils/+/1983240
Tested-by: Alex Klein <saklein@chromium.org>
Reviewed-by: Chris McDonald <cjmcdonald@chromium.org>
Commit-Queue: Alex Klein <saklein@chromium.org>
1 file changed