x11/xinput: Update to 1.6.3

Update x11/xinput to 1.6.3
Add license information
This adds a warning if run under xwayland.
This is a maintenance release

Changelog:
https://lists.x.org/archives/xorg-announce/2019-July/003013.html

Obtained from: FreeBSD Graphics Team development repo

		https://github.com/FreeBSDDesktop/freebsd-ports/tree/feature/xorglibs