mb/*/*/romstage.c: Clean up targets with i82801gx

Things cleaned up in this patch:
* Add macros for the GENx_DEC registers;
* replace many magic numbers by macros;
* remove many writes to DxxIP since they were 'setting' reset default
  values;
* fix some comments about decode ranges.

Change-Id: I9d6a0ff3d391947f611a2f3c65684f4ee57bc263
Signed-off-by: Arthur Heymans <arthur@aheymans.xyz>
Reviewed-on: https://review.coreboot.org/21065
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Kyösti Mälkki <kyosti.malkki@gmail.com>

0 files changed, 0 insertions, 0 deletions