drm/sysfb: efidrm: Support module builds

Make CONFIG_DRM_EFIDRM a tristate to enable module builds.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://lore.kernel.org/r/20250408091837.407401-3-tzimmermann@suse.de

Author: tdz

drivers/gpu/drm/sysfb/Kconfig

@@ -8,8 +8,8 @@ config DRM_SYSFB_HELPER
 	depends on DRM
 
 config DRM_EFIDRM
-	bool "EFI framebuffer driver"
-	depends on (DRM=y) && MMU && EFI && (!SYSFB_SIMPLEFB || COMPILE_TEST)
+	tristate "EFI framebuffer driver"
+	depends on DRM && MMU && EFI && (!SYSFB_SIMPLEFB || COMPILE_TEST)
 	select APERTURE_HELPERS
 	select DRM_CLIENT_SELECTION
 	select DRM_GEM_SHMEM_HELPER