drm/i915: Ensure damage clip area is within pipe area

drm/i915: Ensure damage clip area is within pipe area

Current update area calculation is not handling situation where
e.g. cursor plane is fully or partially outside pipe area.

Fix this by checking damage area against pipe_src area using
drm_rect_intersect.

v2: Set x1 and x2 in damaged_area initialization
v3: Move drm_rect_intersect into clip_area_update
v4: draw_area -> pipe_src

Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/5440
Cc: José Roberto de Souza <jose.souza@intel.com>
Cc: Mika Kahola <mika.kahola@intel.com>
Reviewed-by: José Roberto de Souza <jose.souza@intel.com>
Signed-off-by: Jouni Högander <jouni.hogander@intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220513142811.779331-3-jouni.hogander@intel.com