If AMD_PUBKEY_FILE contains an absolute path the resulting path is
incorrect since it contains $(top).
BUG=b:147042464
TEST=Build trembyle with absolute and relative path.
Signed-off-by: Raul E Rangel <rrangel@chromium.org>
Change-Id: Ib46b1799fad5588a18411f8c32541192d699cdd4
Reviewed-on: https://review.coreboot.org/c/coreboot/+/40910
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Furquan Shaikh <furquan@google.com>
dedbf63522