drm/virtio: Use the hotspot properties from cursor planes

jira VULN-136708
cve-bf CVE-2025-38449
commit-author Zack Rusin <zackr@vmware.com>
commit cc6c535

Atomic modesetting got support for mouse hotspots via the hotspot
properties. Port the legacy kms hotspot handling to the new properties
on cursor planes.

	Signed-off-by: Zack Rusin <zackr@vmware.com>
	Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
	Cc: David Airlie <airlied@linux.ie>
	Cc: Gurchetan Singh <gurchetansingh@chromium.org>
	Cc: Chia-I Wu <olvaffe@gmail.com>
	Cc: Daniel Vetter <daniel@ffwll.ch>
	Cc: virtualization@lists.linux-foundation.org
	Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
	Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20231023074613.41327-7-aesteve@redhat.com
(cherry picked from commit cc6c535)
	Signed-off-by: Roxana Nicolescu <rnicolescu@ciq.com>

Author: roxanan1996

drivers/gpu/drm/virtio/virtgpu_plane.c

@@ -333,16 +333,16 @@ static void virtio_gpu_cursor_plane_update(struct drm_plane *plane,
 		DRM_DEBUG("update, handle %d, pos +%d+%d, hot %d,%d\n", handle,
 			  plane->state->crtc_x,
 			  plane->state->crtc_y,
-			  plane->state->fb ? plane->state->fb->hot_x : 0,
-			  plane->state->fb ? plane->state->fb->hot_y : 0);
+			  plane->state->hotspot_x,
+			  plane->state->hotspot_y);
 		output->cursor.hdr.type =
 			cpu_to_le32(VIRTIO_GPU_CMD_UPDATE_CURSOR);
 		output->cursor.resource_id = cpu_to_le32(handle);
 		if (plane->state->fb) {
 			output->cursor.hot_x =
-				cpu_to_le32(plane->state->fb->hot_x);
+				cpu_to_le32(plane->state->hotspot_x);
 			output->cursor.hot_y =
-				cpu_to_le32(plane->state->fb->hot_y);
+				cpu_to_le32(plane->state->hotspot_y);
 		} else {
 			output->cursor.hot_x = cpu_to_le32(0);
 			output->cursor.hot_y = cpu_to_le32(0);