This patch adds MDMA/UDMA support using BestComm for DMA on the MPC5200
platform.  Based heavily on previous work by Freescale (Bernard Kuhn,
John Rigby) and Domen Puncer.

With this patch, a SanDisk Extreme IV CF card gets read speeds of
approximately 26.70 MB/sec.
Signed-off-by: Tim Yamin <plasm@roo.me.uk>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>