elog: Allow calling boot_count_read() without CONFIG_ELOG_BOOT_COUNT

Have boot_count_read() just return 0 if CONFIG_ELOG_BOOT_COUNT is not
enabled.

BUG=b:79865267
TEST=firmware_EventLog

Change-Id: I70f16226371324dea37b3f36f85c2037e324ef31
Signed-off-by: Daniel Kurtz <djkurtz@chromium.org>
Reviewed-on: https://review.coreboot.org/26526
Reviewed-by: Martin Roth <martinroth@google.com>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
1 file changed