merge xorg-server 1.20.3.

apply

https://cgit.freedesktop.org/xorg/xserver/commit/?id=d7ac755f0b618eb1259d93c8a16ec6e39a18627c

Use timingsafe_memcmp() to compare MIT-MAGIC-COOKIES CVE-2017-2624
Provide the function definition for systems that don't have it.

Signed-off-by: Matthieu Herrb <matthieu@herrb.eu>
Reviewed-by: Alan Coopersmith <alan.coopersmith@oracle.com>

and
https://cgit.freedesktop.org/xorg/xserver/commit/?id=5c44169caed811e59a65ba346de1cadb46d266ec

os: Squash missing declaration warning for timingsafe_memcmp
timingsafe_memcmp.c:21:1: warning: no previous prototype for `timingsafe_memcmp' [-Wmissing-prototypes]
timingsafe_memcmp(const void *b1, const void *b2, size_t len)

Signed-off-by: Adam Jackson <ajax@redhat.com>

apply
https://cgit.freedesktop.org/xorg/xserver/commit/?id=2855f759b1e7bf7f5e57cac36c1f0d0e5ac1a683


auth: remove AuthToIDFunc and associated functions. Not used anymore.
And the current code for MitToId has a use-after-free() issue.

[Also remove the actual implementations - ajax]

Signed-off-by: Matthieu Herrb <matthieu@herrb.eu>
Reviewed-by: Alan Coopersmith <alan.coopersmith@oracle.com>

initial import of xorg-server-1.18.4

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-1.4.2