smm: Make local variables relative to ebp

This reduces the cognitive overhead of referencing locals via esp since
it changes with every push.

BUG=b:80539294
TEST=built and booted on grunt.

Change-Id: Ib7eb98ce3483d4fc803696c1b2496d8384317536
Signed-off-by: Raul E Rangel <rrangel@chromium.org>
Reviewed-on: https://review.coreboot.org/27225
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Martin Roth <martinroth@google.com>
1 file changed