merge xf86-video-ati 22.0.0.

various updates to build against xorg-server 21.1.3.

- avoid a const issue with an expanded __UNCONST().
- cope with renamed member names
- deal with "xf86RamDac.h" going away (now use "xf86Cursor.h")

Backport upstream commits (there is no newer release yet):

From c0eb5dbd9c1db6b6d5b1574bcd8c584170d7ab54 Mon Sep 17 00:00:00 2001
From: Alexey Sheplyakov <asheplyakov@altlinux.org>
Date: Wed, 27 Nov 2019 20:50:58 +0400
Subject: Don't crash X server if GPU acceleration is not available

From 4d84cf438e7f1bebf0053035ef0292e9fed257d1 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Michel=20D=C3=A4nzer?= <mdaenzer@redhat.com>
Date: Fri, 29 Nov 2019 16:37:32 +0100
Subject: Handle NULL fb_ptr in pixmap_get_fb

This can happen when HW acceleration is disabled.

From Onno van der Linden in xsrc/55059.

initial import of xf86-video-ati-19.1.0

initial import of xf86-video-ati-19.0.1

initial import of xf86-video-ati-18.1.0

initial import of xf86-video-ati-18.0.0

initial import of xf86-video-ati-7.9.0

initial import of xf86-video-ati-7.8.0

initial import of xf86-video-ati-6.14.6

initial import of xf86-video-ati-7.8.0

initial import of xf86-video-ati-7.7.0

initial import of xf86-video-ati 7.5.0 sources, into a new subdir as
this only has a chance of working on systems with KMS -- -7 on x86
only, so we need to keep the 6.x around for everyone else.