arc-mesa: arc-mesa-9999 compiles

arc-mesa-9999 is based on Mesa master.
Mesa master no longer supports arguments like "dri_driver=,i915".
The leading comma generates an error.

This CL fixes that. It is based on: https://crrev.com/c/2275258

BUG=None
TEST=cros_workon-$BOARD start arc-mesa
     remove all patches from arc-mesa-9999.ebuild
     emerge-$BOARD arc-mesa
     compiles Ok.

Change-Id: I5dda7f7e76bb5eda6d673935769a5207a48af223
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/overlays/chromiumos-overlay/+/2286395
Commit-Queue: Ricardo Quesada <ricardoq@chromium.org>
Commit-Queue: Lepton Wu <lepton@chromium.org>
Tested-by: Ricardo Quesada <ricardoq@chromium.org>
Reviewed-by: Ilja H. Friedel <ihf@chromium.org>
Reviewed-by: Lepton Wu <lepton@chromium.org>
Auto-Submit: Ricardo Quesada <ricardoq@chromium.org>
1 file changed