As most platforms will share the subset of enabling both low RAM WB and high ROM WP MTRRs, provide them with a single function. Add possibility for the platform to skip these if required. Change-Id: Id1f8b7682035e654231f6133a42909a36e3e15a1 Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com> Reviewed-on: https://review.coreboot.org/c/coreboot/+/34809 Reviewed-by: Aaron Durbin <adurbin@chromium.org> Tested-by: build bot (Jenkins) <no-reply@coreboot.org>