qla2xxx: Configure NPIV fc_vport via tcm_qla2xxx_npiv_make_lport

qla2xxx: Configure NPIV fc_vport via tcm_qla2xxx_npiv_make_lport

This patch changes qla2xxx qlt_lport_register() code to accept
target_lport_ptr + npiv_wwpn + npiv_wwnn parameters, and updates
tcm_qla2xxx to use the new tcm_qla2xxx_lport_register_npiv_cb()
callback for invoking fc_vport_create() from configfs context
via tcm_qla2xxx_npiv_make_lport() code.

In order for this to work, the qlt_lport_register() callback is
now called without holding qla_tgt_mutex, as the fc_vport creation
process will call qlt_vport_create() -> qlt_add_target(), which
already expects to acquire it.

It enforces /sys/kernel/config/target/qla2xxx_npiv/$NPIV_WWPN
naming in the following format:

     $PHYSICAL_WWPN@$NPIV_WWPN:$NPIV_WWNN

and assumes the $PHYSICAL_WWPN in question has already had been
configured for target mode in non NPIV mode.

Finally, it updates existing tcm_qla2xxx_lport_register_cb() logic
to setup the non NPIV assignments that have now been moved out of
qlt_lport_register() code.

Cc: Sawan Chandak <sawan.chandak@qlogic.com>
Cc: Quinn Tran <quinn.tran@qlogic.com>
Cc: Saurav Kashyap <saurav.kashyap@qlogic.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>