DGA support

[Samuel Rydh]

MOL now has preliminary X11 DGA support (in the BK/rsync tree). 
This should make it easier to get fullscreen video working
(in particular if a flat-panel display is used). 

I'm a bit uncertain how well XDGA works on the powerpc platform
though; I would appreciate some testing on various
hardware/XFree86 combinations.

On XF86 4.0.3 with an ATI Rage 128, the only video mode
that works properly is the one the X-server is using. Other modes
are reported but they are all quite borken.

To test the xdga support, add the following to
/etc/mol/molrc.video:

	enable_xdga_video:	yes
	enable_console_video:	no
	enable_xvideo:		no

	# affects which DGA mode to be used at startup...
	resolution:		1024/768/85
	depth:			24

To exit DGA-mode, press Cmd+Cntrl+Space in MOL.

Cheers,

/Samuel