With support for MRT in the driver (not included here), passes:
dEQP-GLES31.functional.shaders.builtin_functions.integer.imulextended.int_highp_fragment
dEQP-GLES31.functional.shaders.builtin_functions.integer.umulextended.int_highp_fragment
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/19590>