scsi: lpfc: Change lpfc_vport load_flag member into a bitmask

scsi: lpfc: Change lpfc_vport load_flag member into a bitmask

In attempt to reduce the amount of unnecessary shost_lock acquisitions in
the lpfc driver, change load_flag into an unsigned long bitmask and use
clear_bit/test_bit bitwise atomic APIs instead of reliance on shost_lock
for synchronization.

Also, correct the test for FC_UNLOADING in lpfc_ct_handle_mibreq, which
incorrectly tests vport->fc_flag rather than vport->load_flag.

Signed-off-by: Justin Tee <justin.tee@broadcom.com>
Link: https://lore.kernel.org/r/20240131185112.149731-16-justintee8345@gmail.com
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>