scsi: bfa: bfad.c: make max_rport_logins static

Fix the following sparse warning:

drivers/scsi/bfa/bfad.c:53:17: warning: symbol 'max_rport_logins' was
not declared. Should it be static?

Link: https://lore.kernel.org/r/20200407032202.36789-8-yanaijie@huawei.comReported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/bfa/bfad.c

@@ -50,7 +50,7 @@ int		pcie_max_read_reqsz;
 int		bfa_debugfs_enable = 1;
 int		msix_disable_cb = 0, msix_disable_ct = 0;
 int		max_xfer_size = BFAD_MAX_SECTORS >> 1;
-int		max_rport_logins = BFA_FCS_MAX_RPORT_LOGINS;
+static int	max_rport_logins = BFA_FCS_MAX_RPORT_LOGINS;
 
 /* Firmware releated */
 u32	bfi_image_cb_size, bfi_image_ct_size, bfi_image_ct2_size;