Drop i855pm port and rename i855gme to i855 instead.

Drop  i855pm port and rename i855gme to i855 instead.
This patch also changes the digitallogic/adl855pc to use that port.
It probably won't work, but at least we will get an error if something
breaks compilation of the i855 code that is there.

Signed-off-by: Stefan Reinauer <stepan@coresystems.de>
Acked-by: Ronald G. Minnich <rminnich@gmail.com>
git-svn-id: svn://svn.coreboot.org/coreboot/trunk@5163 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1