[SCSI] lpfc 8.1.4 : Two misc fixes

Two misc fixes:
 - Fix deadlock caused by return with host_lock held in lpfc_findnode_did
 - Initialize all fields of the allocated mail box structure to zero.
   Was causing some sysfs mailbox commands to fail immediately after load.

Signed-off-by: James Smart <James.Smart@emulex.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>