print warning but do not fail if NVRam can not be parsed (#271)
print warning but do not fail if NVRam can not be parsed (#271)

It's ok if we can't parse NVRam variables, just print a warning.

Signed-off-by: Ronald G. Minnich <f569d0af9a3481c4007b95c7180d6c41009f2513@gmail.com>
linuxboot/fiano