x11/xorgproto: update to 2021.4

Changes:	https://lists.x.org/archives/xorg-announce/2021-February/003072.html
Changes:	https://lists.x.org/archives/xorg-announce/2021-February/003073.html
Changes:	https://lists.x.org/archives/xorg-announce/2021-April/003085.html
PR:		255771
Reported by:	portscout
Approved by:	zeising
Exp-run by:	antoine
Differential Revision:	https://reviews.freebsd.org/D30203