drm/hyperv: Use offset-adjusted shadow-plane mappings

For framebuffers with non-zero offset fields, shadow-plane helpers
provide a pointer to the first byte of the contained data. Use it in
hyperv.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20210803125928.27780-5-tzimmermann@suse.de

drivers/gpu/drm/hyperv/hyperv_drm_modeset.c

@@ -105,7 +105,7 @@ static void hyperv_pipe_enable(struct drm_simple_display_pipe *pipe,
 				crtc_state->mode.hdisplay,
 				crtc_state->mode.vdisplay,
 				plane_state->fb->pitches[0]);
-	hyperv_blit_to_vram_fullscreen(plane_state->fb, &shadow_plane_state->map[0]);
+	hyperv_blit_to_vram_fullscreen(plane_state->fb, &shadow_plane_state->data[0]);
 }
 
 static int hyperv_pipe_check(struct drm_simple_display_pipe *pipe,
@@ -133,7 +133,7 @@ static void hyperv_pipe_update(struct drm_simple_display_pipe *pipe,
 	struct drm_rect rect;
 
 	if (drm_atomic_helper_damage_merged(old_state, state, &rect)) {
-		hyperv_blit_to_vram_rect(state->fb, &shadow_plane_state->map[0], &rect);
+		hyperv_blit_to_vram_rect(state->fb, &shadow_plane_state->data[0], &rect);
 		hyperv_update_dirt(hv->hdev, &rect);
 	}
 }