[PATCH] Automatic RAM detection for VT8601

[SONE Takeshi]

Hi,
This patch adds automatic detection of installed RAM presence,
size, and MA mapping type for VIA VT8601 northbridge.

I tested this with VIA EPIA 5000 and 3 different type DIMMs.

A. 64MB single sided (borrowed from my server :)
B. 256MB double sided (borrowed from my desktop :)
C. 256MB single sided (bought for EPIA)

Timing was set to PC100 CL=3. (it's configurable at build time)
EPIA has 2 DIMM slots, and 'empty' is possible in addition to 3 DIMMs,
so there are 12 (=4*3) possible installation patterns.
All patterns are tested with memtest86 3.0 as payload,
to at least Test #2, and no error was found.
Additionally DIMM B+C (512MB total) with PC133 CL=2 configuration
was tested and all tests of memtest86's Std Test found no error.