drm/ssd130x: Use drm_atomic_get_new_plane_state()

The struct drm_plane .state shouldn't be accessed directly but instead the
drm_atomic_get_new_plane_state() helper function should be used.

This is based on a similar patch from Thomas Zimmermann for the simpledrm
driver. No functional changes.
Suggested-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20220923083447.1679780-1-javierm@redhat.com

drivers/gpu/drm/solomon/ssd130x.c

@@ -566,10 +566,10 @@ static int ssd130x_fb_blit_rect(struct drm_framebuffer *fb, const struct iosys_m
 }
 
 static void ssd130x_primary_plane_helper_atomic_update(struct drm_plane *plane,
-						       struct drm_atomic_state *old_state)
+						       struct drm_atomic_state *state)
 {
-	struct drm_plane_state *plane_state = plane->state;
-	struct drm_plane_state *old_plane_state = drm_atomic_get_old_plane_state(old_state, plane);
+	struct drm_plane_state *plane_state = drm_atomic_get_new_plane_state(state, plane);
+	struct drm_plane_state *old_plane_state = drm_atomic_get_old_plane_state(state, plane);
 	struct drm_shadow_plane_state *shadow_plane_state = to_drm_shadow_plane_state(plane_state);
 	struct drm_device *drm = plane->dev;
 	struct drm_rect src_clip, dst_clip;
@@ -591,7 +591,7 @@ static void ssd130x_primary_plane_helper_atomic_update(struct drm_plane *plane,
 }
 
 static void ssd130x_primary_plane_helper_atomic_disable(struct drm_plane *plane,
-							struct drm_atomic_state *old_state)
+							struct drm_atomic_state *state)
 {
 	struct drm_device *drm = plane->dev;
 	struct ssd130x_device *ssd130x = drm_to_ssd130x(drm);