[target/qsd8250]: Add support to represent partition size in MB

Add code to dynamically configure the partition table using
the flash page size information and represent the sizes in MB
instead of blocks.  This makes it easier to read and recalculate
the block for partition if we detect that we are running on a
4K page nand device.

Change-Id: Ic7477e220ba714c29a0f3e66f7874e9b16846fa7
2 files changed