target/sbp: Remove strict param from sbp_parse_wwn

It's always set, and controls whether uppercase A-F are allowed hex values.
I don't see a reason not to accept these.

Signed-off-by: Andy Grover <agrover@redhat.com>
Cc: Chris Boot <bootc@bootc.net>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>