drm/tests: Set also mock plane src_x, src_y, src_w and src_h

We need to set also src_x, src_y, src_w and src_h for the mock plane.
After fix for drm_atomic_helper_damage_iter_init we are using these
when iterating damage_clips.
Signed-off-by: Jouni Högander <jouni.hogander@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220823112920.352563-5-jouni.hogander@intel.comReviewed-by: Mika Kahola <mika.kahola@intel.com>
Tested-by: Maíra Canal <mairacanal@riseup.net>

drivers/gpu/drm/tests/drm_damage_helper_test.c

@@ -59,6 +59,11 @@ static int drm_damage_helper_init(struct kunit *test)
 static void set_plane_src(struct drm_plane_state *state, int x1, int y1, int x2,
 			  int y2)
 {
+	state->src_x = x1;
+	state->src_y = y1;
+	state->src_w = x2 - x1;
+	state->src_h = y2 - y1;
+
 	state->src.x1 = x1;
 	state->src.y1 = y1;
 	state->src.x2 = x2;