spi: Move ICH BBAR quirk out of the way

Get rid of the layering violations around ICH's BBAR. Move all the weird
address handling into (surprise, surprise) `ichspi.c`. Might fix writes
for the `BBAR != 0` case by accident.

Background: Some ICHs have a BBAR (BIOS Base Address Configuration
Register) that, if set, limits the valid address range to [BBAR, 2^24).
Current code lifted addresses for REMS, RES and READ operations by BBAR,
now we do it for all addresses in ichspi. Special care has to be taken
if the BBAR is not aligned by the flash chip's size. In this case, the
lower part of the chip (from BBAR aligned down, up to BBAR) is inacces-
sible (this seems to be the original intend behind BBAR) and has to be
left out in the address offset calculation.

Change-Id: Icbac513c5339e8aff624870252133284ef85ab73
Signed-off-by: Nico Huber <nico.h@gmx.de>
---
M flash.h
M ichspi.c
M programmer.h
M spi.c
M spi25.c
5 files changed, 28 insertions(+), 83 deletions(-)