r600g: Fix assert in tgsi_cmp
Fixes https://bugs.freedesktop.org/show_bug.cgi?id=91726 Signed-off-by:Glenn Kennard <glenn.kennard@gmail.com> Cc: "11.0" <mesa-stable@lists.freedesktop.org> Signed-off-by:
Dave Airlie <airlied@gmail.com> (cherry picked from commit 50932268)