[U-Boot] [0/6] Patch serie UBI min I/O size fixes

[Holger Brunck]

This patch serie fixes a problem in the UBI layer. The min I/O size has
currently a fixed value of 1 for NOR flashes. But for NOR flashes the min I/O
size has to be equal to the size of the writebuffer of the flash. Therefore the
mtd layer was enhanced with the writebuffer which was later on used in the ubi
layer to set the min I/O size.

This patches fixes problems with flash types with a writebuffersize > 128 Byte
and is mainly taken from the similar linux patches. See MTD mailing list posts:
http://lists.infradead.org/pipermail/linux-mtd/2010-December/033460.html

Without the u-boot patches attaching to a ubi device with a min I/O buffer
larger than 128 would fail.

Best
Regards