build_packages.sh: Remove duplicated arg parsing

Remove duplicated argument parsing logic that has already been migrated
to Python.

BUG=b:218520588
TEST=manual

Change-Id: Ibf65935cf51f9814e18ca2dcbed3c874d6e9e860
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/crosutils/+/3498551
Reviewed-by: Ram Chandrasekar <rchandrasekar@google.com>
Tested-by: Cindy Lin <xcl@google.com>
Commit-Queue: Cindy Lin <xcl@google.com>
1 file changed