Exclude Mali devices from manual mip-mapping.

With manual mip-mapping, the Nexus 10 is failing the sRGB mip-map test. That suggests a failure in the sRGB implementation (decode after bilerp, possibly?). Using the driver's mip-mapper resolves the unit test issue, at least.

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2036763002

Review-Url: https://codereview.chromium.org/2036763002
1 file changed