[U-Boot] [PATCH 0/2] spl: MMC U-Boot image load from raw partition

This is a first attempt at adding support for U-Boot image load from raw partitions. It does not support OS boot as I cannot test it on my current setup.

This is going to be useful for the Optimus Black port (please do not consider this as dead code because no board is using it right now, there will be one soon)! On the Optimus Black, the second stage bootloader (U-Boot in our case) is stored on the second partition of the internal EMMC. This patch allows reading from that partition without the need of providing the U-Boot config with a sector address, but with the partition address.

It makes sense as there is already code to read partition tables, so it would be a shame to hardcode the sector address while it can be obtained dynamically.