README for HVUBL

This UBL can be used for flashing itself and a 2nd stage bootloader (usually
U-boot) in flash memory.

It can also be used to flash an arbitrary data image into flash, without
a header.

It can also be used to run DDR RAM memory testing.

To compile HVUBL for the sffsdr board, for example, run:
  $> make BOARD=sffsdr

The Makefile honors the CROSS_COMPILE environment variable to specify the prefix
of your ARM gcc toolchain. If it is not set, it defaults to:
  CROSS_COMPILE=arm-linux-

You can override it like this, for example:
  $> make CROSS_COMPILE=arm-angstrom-linux-gnueabi- BOARD=sffsdr

The output file, in ARM ELF format, will be named <ubl.elf>