IB/hfi1: Use hdr2sc function to calculate 5-bit SC

The interface is used to compute the 5-bit SC field from the
LRH and the RHF bits. Modify code to use the interface instead.

Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Dasaratharaman Chandramouli <dasaratharaman.chandramouli@intel.com>
Signed-off-by: Don Hiatt <don.hiatt@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
diff --git a/drivers/infiniband/hw/hfi1/driver.c b/drivers/infiniband/hw/hfi1/driver.c
index 4dbadf7..8246dc7 100644
--- a/drivers/infiniband/hw/hfi1/driver.c
+++ b/drivers/infiniband/hw/hfi1/driver.c
@@ -392,9 +392,7 @@
 			u16 rlid;
 			u8 svc_type, sl, sc5;
 
-			sc5  = (be16_to_cpu(rhdr->lrh[0]) >> 12) & 0xf;
-			if (rhf_dc_info(packet->rhf))
-				sc5 |= 0x10;
+			sc5 = hdr2sc(rhdr, packet->rhf);
 			sl = ibp->sc_to_sl[sc5];
 
 			lqpn = be32_to_cpu(bth[1]) & RVT_QPN_MASK;