uboot-imx

Blackfin: move CONFIG_BFIN_CPU to board config.mk

The CONFIG_BFIN_CPU option is largely used in the build system, so move
it out of the board config.h and into the board config.mk.  It'd be nice
to keep everything in the config.h, but the patch to extract that value
early was rejected.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>