caif: set traffic class for caif packets

Set traffic class for CAIF packets, based on socket
priority, CAIF protocol type, or type of message.

Traffic class mapping for different packet types:
 - control:       TC_PRIO_CONTROL;
 - flow control:  TC_PRIO_CONTROL;
 - at:            TC_PRIO_CONTROL;
 - rfm:           TC_PRIO_INTERACTIVE_BULK;
 - other sockets: equals to socket's TC;
 - network data:  no change.

Signed-off-by: Dmitry Tarnyagin <dmitry.tarnyagin@stericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/caif/cfsrvl.c

@@ -11,6 +11,7 @@
 #include <linux/errno.h>
 #include <linux/slab.h>
 #include <linux/module.h>
+#include <linux/pkt_sched.h>
 #include <net/caif/caif_layer.h>
 #include <net/caif/cfsrvl.h>
 #include <net/caif/cfpkt.h>
@@ -120,6 +121,7 @@ static int cfservl_modemcmd(struct cflayer *layr, enum caif_modemcmd ctrl)
 			info->channel_id = service->layer.id;
 			info->hdr_len = 1;
 			info->dev_info = &service->dev_info;
+			cfpkt_set_prio(pkt, TC_PRIO_CONTROL);
 			return layr->dn->transmit(layr->dn, pkt);
 		}
 	case CAIF_MODEMCMD_FLOW_OFF_REQ:
@@ -140,6 +142,7 @@ static int cfservl_modemcmd(struct cflayer *layr, enum caif_modemcmd ctrl)
 			info->channel_id = service->layer.id;
 			info->hdr_len = 1;
 			info->dev_info = &service->dev_info;
+			cfpkt_set_prio(pkt, TC_PRIO_CONTROL);
 			return layr->dn->transmit(layr->dn, pkt);
 		}
 	default: