Get rid of the old romstage-as-bootblock ROM layout

Get rid of the old romstage-as-bootblock ROM layout

This change removes CONFIG_TINY_BOOTBLOCK, CONFIG_BIG_BOOTBLOCK, and
all their uses, assuming TINY_BOOTBLOCK=y, BIG_BOOTBLOCK=n.

This might break a couple of boards on runtime, but so far, fixes were
quite simple.
There's a flag day: Code that relies on CONFIG_TINY_BOOTBLOCK must be
adapted.

Change-Id: I1e17a4a1b9c9adb8b43ca4db8aed5a6d44d645f5
Signed-off-by: Patrick Georgi <patrick@georgi-clan.de>
Reviewed-on: http://review.coreboot.org/320
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>