[U-Boot] mmc changes in v2014.04-rc3 cause problems when using mmc in SPL

[Hans de Goede]

Hi,

While merging v2014.04-rc3 into our sunxi u-boot branch, I hit a problem
where mmc would no longer work in the SPL.

The problem is that the new mmc_create call forces use of HEAP memory,
while in the SPL there may be no HEAP.

For now I've created a small 2048 bytes HEAP in our SPL, but if possible
I would like to get rid of the need for a HEAP though, as we only have
24K of RAM for our SPL.

Regards,

Hans