drivers/tpm/spi: Convert static functions to enum cb_err return types
Instead of using raw integers to indicate success/failure, enum cb_err
can be used to makes things clearer, so this patch converts most
functions to return that instead of int.
TEST=boot to OS on google/dratini, no TPM errors seen
Signed-off-by: Tim Wawrzynczak <twawrzynczak@chromium.org>
Change-Id: Ifb749c931fe008b16d42fcf157af820ec8fbf5ac
Reviewed-on: https://review.coreboot.org/c/coreboot/+/61976
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Felix Held <felix-coreboot@felixheld.de>