scsi: lpfc: Prevent duplicate requests to unregister with cpuhp framework

In the lpfc offline routine, called for various reasons such as sysfs
attribute, driver unload, or port error, the driver is calling
__lpfc_cpuhp_remove() to destroy the hot plug data. If the offline routine
is called while the driver is in the process of being unloaded, a request
using lpfc_cpuhp_remove() is also made from lpfc_sli4_hba_unset(). The
cpuhp elements are no longer valid when the second removal request is made.

Fix by only calling the cpuhp removal once when the adapter is in the
process of unloading.

Link: https://lore.kernel.org/r/20210104180240.46824-8-jsmart2021@gmail.com


Co-developed-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <jsmart2021@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>