scripts: package_has_missing_deps: Add --no-default-board

When running as a hook script we need to be able to disable the default
board logic to avoid breaking the SDK.

BUG=b:300310156
TEST=package_has_missing_deps with and without --no-default_board

Change-Id: Ie6e5f057413db14d4bd013b63b45b0b1dfab7b0f
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/chromite/+/4873217
Commit-Queue: Allen Webb <allenwebb@google.com>
Tested-by: Allen Webb <allenwebb@google.com>
Reviewed-by: Mike Frysinger <vapier@chromium.org>
diff --git a/scripts/package_has_missing_deps.py b/scripts/package_has_missing_deps.py
index 8bf85ba..bc1818c 100644
--- a/scripts/package_has_missing_deps.py
+++ b/scripts/package_has_missing_deps.py
@@ -307,6 +307,14 @@
     )
 
     parser.add_argument(
+        "--no-default-board",
+        dest="board",
+        const=None,
+        action="store_const",
+        help="Ignore the default board",
+    )
+
+    parser.add_argument(
         "-i",
         "--build-info",
         default=None,