Restore -flipPixels option removed in upstream server-21.1-branch.

https://gitlab.freedesktop.org/xorg/xserver/-/commit/d1c00c859c6676fbb540420c9055788bc19cb18f
Note ScrnInfoRec structure in hw/xfree86/common/xf86str.h isn't reverted
because it isn't used by -flipPixels option so that we can keep ABI
compatibility among xf86-video-foo drivers.

This -flipPixels is mandatory at least by Xorg server users with
xf86-video-wsfb driver on NetBSD/mac68k and SE/30 mono screen
that has "black=1 and white=0" VRAM.

"go for it" by mrg@ on current-users@:
https://mail-index.netbsd.org/current-users/2022/07/24/msg042731.html

initial import of xorg-server-21.1.3

initial import of xorg-server-1.20.10

initial import of xorg-server-1.20.6

initial import of xorg-server-1.20.3

initial import of xorg-server-1.18.4

initial import of xorg-server-1.10.6

initial import of xorg-server 1.10.3. highlights include:
- fixes xorg bugs 29969, 30367, 30527, 30267, 30260, 29046,
30260, 31548, 28672, 24887, 32115, 21457, 32436, 21827,
28414, 24703, 32803, 16318, 33449, 33324, 33929, 35082,
35209, 36146, 36119
- many additional NULL checks
- adjustments related to input ABI 12
- *lots* of dead code removal
- vga arbitrator fixes
- GL fixes
- EDID fixes
- conversion to using asprintf() in many places
- many fixes from valgrind, compiler warnings

see these for more details:
http://lists.freedesktop.org/archives/xorg-announce/2011-February/001612.html
http://lists.freedesktop.org/archives/xorg-announce/2011-April/001646.html
http://lists.freedesktop.org/archives/xorg-announce/2011-May/001675.html
http://lists.freedesktop.org/archives/xorg-announce/2011-July/001710.html

import xorg-server 1.9.2. important changes since 1.6.5 include:

- built-in symbol visibility, default not export
- fixes for various crashes
- many fixes for XI2, EXA, dix, render, glx, xkb, EDID, randr, Xv,
resource handling, Xext, vfb, xfree86 / vga and composite support.
- fixes several memory leaks
- many many documentation updates
- record extension enabled
- no longer looks for XF86Config files

initial import of xorg-server-1.6.1.901

initial import of xorg-server-1.4.2