cpu/amd/mtrr.h: Drop excessive includes

Change-Id: Id404bdab1f2361f1e7d20f7ee72111971863dddf
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/17736
Tested-by: build bot (Jenkins)
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
58 files changed