scsi: lpfc: Remove set but not used 'qp'

This addresses the following gcc warning with "make W=1":

not used [-Wunused-but-set-variable]
  struct lpfc_sli4_hdw_queue *qp;
                                ^

Link: https://lore.kernel.org/r/20200909082716.37787-1-yebin10@huawei.com


Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Ye Bin <yebin10@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
drivers/scsi/lpfc/lpfc_debugfs.c: In function ‘lpfc_debugfs_hdwqstat_data’:
drivers/scsi/lpfc/lpfc_debugfs.c:1699:30: warning: variable ‘qp’ set but