qla2xxx: Add missing ->vport_slock while calling qlt_update_vp_map

qla2xxx: Add missing ->vport_slock while calling qlt_update_vp_map

All other callers of qlt_update_vp_map() already hold ->vport_slock
while updating the vp target map, so go ahead and add the missing
->vport_slock within qla24xx_disable_vp() code.

Cc: Saurav Kashyap <[email protected]>
Cc: Chad Dupuis <[email protected]>
Cc: Arun Easi <[email protected]>
Cc: Andrew Vasquez <[email protected]>
Cc: Jiri Kosina <[email protected]>
Cc: Roland Dreier <[email protected]>
Acked-by: Saurav Kashyap <[email protected]>
Signed-off-by: Nicholas Bellinger <[email protected]>