MMC Controller driver for PXA255

[Jacques Fourie]

Hi,

I've written a driver for the MMC controller found on the Intel Xscale
PXA255 (as found on the Gumstix Connex). It seems to work OK - I've
tested with a range of SD cards. The driver works in PIO mode (still
busy to debug some DMA issues) and on my Gumstix Connex I get around
400kB/s. If anyone wants to review the code for inclusion let me know
and I'll be happy to provide it.

Jacques