fix(iscsi): install 8021q module unconditionally

In iBFT setups, VLAN can be configured in the firmware.
Add the 8021q module in hostonly mode even if VLAN is currently
not used to be prepared for such configuration change.

modules.d/95iscsi/module-setup.sh

@@ -161,7 +161,7 @@ installkernel() {
     local _funcs='iscsi_register_transport'
 
     instmods bnx2i qla4xxx cxgb3i cxgb4i be2iscsi qedi
-    hostonly="" instmods iscsi_tcp iscsi_ibft crc32c iscsi_boot_sysfs
+    hostonly="" instmods iscsi_tcp iscsi_ibft crc32c iscsi_boot_sysfs 8021q
 
     if [ "$_arch" = "s390" -o "$_arch" = "s390x" ]; then
         _s390drivers="=drivers/s390/scsi"