drm/vkms: Fix an undefined reference error in vkms_composer_worker

I hit the following error when compile the kernel.

drivers/gpu/drm/vkms/vkms_composer.o: In function `vkms_composer_worker':
vkms_composer.c:(.text+0x5e4): undefined reference to `crc32_le'
make: *** [vmlinux] Error 1
Signed-off-by: zhong jiang <zhongjiang@huawei.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/1569201883-18779-1-git-send-email-zhongjiang@huawei.com

drivers/gpu/drm/Kconfig

@@ -263,6 +263,7 @@ config DRM_VKMS
 	tristate "Virtual KMS (EXPERIMENTAL)"
 	depends on DRM
 	select DRM_KMS_HELPER
+	select CRC32
 	default n
 	help
 	  Virtual Kernel Mode-Setting (VKMS) is used for testing or for