Cherry-pick Xorg version independent changes from xorg-server.

Normalize #include paths.
Call LogInit() for logging to /var/log/X68k.%s.log as Xorg and Xsun servers.
Fix a suspicious chunk disabled on xfree 4.x migration as sunKbd.c does.
Restore video mode properly on exit even on CRT Mode 19 (640x480 31kHz VGA).
Add ModeDef for 640x480x4bit PseudoColor.
Avoid a use of __UNVOLATILE(3).
Remove unnecessary pointer casts from malloc(3).
Use exact-width interger types properly for register accesses etc.

Remove clause 3 and 4 from X68k server files written by Yasushi Yamasaki.

I've finally contacted with Yamasaki-san and he kindly answered
"no objection to change them to 2 clause license" in private mail.
Diffs to be committed have also been confirmed by him.
We appreciate all his contribution to early NetBSD/x68k.

initial import of existing netbsd xorg-server 1.10 sources in the
xorg-server.old subdir.