Additionally add support for PIPE_CAP_CLEAR_SCISSORED since we are already
touching the scissor state.
Fixes various gnome-shell rendering artifacts.
v2: Remove NEW_SCISSOR as clear now updates scissor registers explicitly
v3: Reset scissor_off state since its not off now after clear
Cc: mesa-stable
Reviewed-by: Ilia Mirkin <imirkin@alum.mit.edu>
Reviewed-by: Karol Herbst <kherbst@redhat.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/18137>