drm: use drm_driver_legacy_fb_format in drm_gem_fbdev_fb_create

Creating framebuffers for fbdev emulation should use the correct format
code too, so switch drm_gem_fbdev_fb_create() over to use the new
drm_driver_legacy_fb_format() function.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20180921134704.12826-3-kraxel@redhat.com

drivers/gpu/drm/drm_gem_framebuffer_helper.c

@@ -316,8 +316,8 @@ drm_gem_fbdev_fb_create(struct drm_device *dev,
 	if (pitch_align)
 		mode_cmd.pitches[0] = roundup(mode_cmd.pitches[0],
 					      pitch_align);
-	mode_cmd.pixel_format = drm_mode_legacy_fb_format(sizes->surface_bpp,
-							sizes->surface_depth);
+	mode_cmd.pixel_format = drm_driver_legacy_fb_format(dev, sizes->surface_bpp,
+							    sizes->surface_depth);
 	if (obj->size < mode_cmd.pitches[0] * mode_cmd.height)
 		return ERR_PTR(-EINVAL);