snow: Add a name to the serial console UART choice block.

This allows other boards to have the same choice block without confusing
kconfig.

Change-Id: Iea5a7f2d1c263aa7992f504b832ca9c862833c3f
Signed-off-by: Gabe Black <gabeblack@chromium.org>
Reviewed-on: http://review.coreboot.org/3293
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
Tested-by: build bot (Jenkins)
1 file changed