i965/fs: Set force_writemask_all on shader_time instructions.

These computations don't have anything to do with the currently
executing channels, so they should use force_writemask_all.

This fixes assert failures.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=86974
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Matt Turner <mattst88@gmail.com>
Cc: mesa-stable@lists.freedesktop.org
1 file changed