The new version comes with the following changes:
* following ustream, xf86-video-modesetting is now provided with xorg-server
package.
* These packages are deprecated and moved to AUR, some are replaced by
modesetting driver: xf86-video-ast, xf86-video-cirrus, xf86-video-geode, xf86
-video-mga, xf86-video-sisimedia, xf86-video-v4l
URL: https://www.archlinux.org/news/xorg-server-1171-is-now-available/