soc/amd/stoneyridge/northbridge: use get_top_of_mem_[below,above]_4gb

Use get_top_of_mem_below_4gb and get_top_of_mem_above_4g instead of
open-coding the functionality.

Signed-off-by: Felix Held <felix-coreboot@felixheld.de>
Change-Id: I04f2a3744aee9beedaa97b154a652ce6f0c705c0
Reviewed-on: https://review.coreboot.org/c/coreboot/+/74613
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Martin Roth <martin.roth@amd.corp-partner.google.com>

0 files changed, 0 insertions, 0 deletions