scsi: be2iscsi: Move VLAN code to common iface_set_param

VLAN tag is L2 construct, move VLAN code out from configuring IP.
Rearrange and rename the APIs to make it consistent.
Replace ENOSYS with EPERM.

Signed-off-by: Jitendra Bhivare <jitendra.bhivare@broadcom.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/be2iscsi/be_mgmt.h

@@ -308,7 +308,7 @@ int be_mgmt_get_boot_shandle(struct beiscsi_hba *phba,
 
 unsigned int mgmt_get_all_if_id(struct beiscsi_hba *phba);
 
-int mgmt_set_vlan(struct beiscsi_hba *phba, uint16_t vlan_tag);
+int beiscsi_if_set_vlan(struct beiscsi_hba *phba, uint16_t vlan_tag);
 
 ssize_t beiscsi_drvr_ver_disp(struct device *dev,
 			       struct device_attribute *attr, char *buf);