[skotty] Speculative g3 DM build fix

Disable Skotty support in G3 for now.

TBR=
Change-Id: Ic64f62bc21e9d4a531cdfa2495710edc1ba531f8
Reviewed-on: https://skia-review.googlesource.com/90029
Reviewed-by: Florin Malita <fmalita@chromium.org>
Commit-Queue: Florin Malita <fmalita@chromium.org>
3 files changed