scripts: cros_sdk: accept --goma-dir

Support both forms for now so we can migrate existing code to the new
one without breaking things.

BUG=b:191307774
TEST=`cros_sdk` still works

Change-Id: I2a8ebf5891de01d877cc04c370df80035109c771
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/chromite/+/4205473
Tested-by: Mike Frysinger <vapier@chromium.org>
Commit-Queue: Mike Frysinger <vapier@chromium.org>
Reviewed-by: Gilberto Contreras <gcontreras@google.com>
diff --git a/scripts/cros_sdk.py b/scripts/cros_sdk.py
index 32144d1..d94a194 100644
--- a/scripts/cros_sdk.py
+++ b/scripts/cros_sdk.py
@@ -870,6 +870,7 @@
         ),
     )
     parser.add_argument(
+        "--goma-dir",
         "--goma_dir",
         type="path",
         help="Goma installed directory to mount into the chroot.",