nonspd_modules: ignore bad speed info from SMBIOS

Some older firmwares report bad speeds from smbios, but it does not
matter, as nothing in the OS really cares about this.

BUG=chromium:1173568
TEST=mosys memory spd print all on liara

Change-Id: I73babf8b5520b68e7276116061c9d1c3ce18d514
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/mosys/+/2749078
Tested-by: Jack Rosenthal <jrosenth@chromium.org>
Reviewed-by: Rob Barnes <robbarnes@google.com>
Commit-Queue: Jack Rosenthal <jrosenth@chromium.org>
1 file changed