fix off-by-one error when mapping from meas rep to neighbor cell
diff --git a/openbsc/src/gsm_04_08_utils.c b/openbsc/src/gsm_04_08_utils.c
index 0444039..9bafe3d 100644
--- a/openbsc/src/gsm_04_08_utils.c
+++ b/openbsc/src/gsm_04_08_utils.c
@@ -735,7 +735,7 @@
 	mrc = &rep->cell[0];
 	mrc->rxlev = data[3] & 0x3f;
 	mrc->neigh_idx = data[4] >> 3;
-	mrc->arfcn = bitvec_get_nth_set_bit(nbv, mrc->neigh_idx);
+	mrc->arfcn = bitvec_get_nth_set_bit(nbv, mrc->neigh_idx + 1);
 	mrc->bsic = ((data[4] & 0x07) << 3) | (data[5] >> 5);
 	if (rep->num_cell < 2)
 		return 0;
@@ -743,7 +743,7 @@
 	mrc = &rep->cell[1];
 	mrc->rxlev = ((data[5] & 0x1f) << 1) | (data[6] >> 7);
 	mrc->neigh_idx = (data[6] >> 2) & 0x1f;
-	mrc->arfcn = bitvec_get_nth_set_bit(nbv, mrc->neigh_idx);
+	mrc->arfcn = bitvec_get_nth_set_bit(nbv, mrc->neigh_idx + 1);
 	mrc->bsic = ((data[6] & 0x03) << 4) | (data[7] >> 4);
 	if (rep->num_cell < 3)
 		return 0;
@@ -751,7 +751,7 @@
 	mrc = &rep->cell[2];
 	mrc->rxlev = ((data[7] & 0x0f) << 2) | (data[8] >> 6);
 	mrc->neigh_idx = (data[8] >> 1) & 0x1f;
-	mrc->arfcn = bitvec_get_nth_set_bit(nbv, mrc->neigh_idx);
+	mrc->arfcn = bitvec_get_nth_set_bit(nbv, mrc->neigh_idx + 1);
 	mrc->bsic = ((data[8] & 0x01) << 6) | (data[9] >> 3);
 	if (rep->num_cell < 4)
 		return 0;
@@ -759,7 +759,7 @@
 	mrc = &rep->cell[3];
 	mrc->rxlev = ((data[9] & 0x07) << 3) | (data[10] >> 5);
 	mrc->neigh_idx = data[10] & 0x1f;
-	mrc->arfcn = bitvec_get_nth_set_bit(nbv, mrc->neigh_idx);
+	mrc->arfcn = bitvec_get_nth_set_bit(nbv, mrc->neigh_idx + 1);
 	mrc->bsic = data[11] >> 2;
 	if (rep->num_cell < 5)
 		return 0;
@@ -767,7 +767,7 @@
 	mrc = &rep->cell[4];
 	mrc->rxlev = ((data[11] & 0x03) << 4) | (data[12] >> 4);
 	mrc->neigh_idx = ((data[12] & 0xf) << 1) | (data[13] >> 7);
-	mrc->arfcn = bitvec_get_nth_set_bit(nbv, mrc->neigh_idx);
+	mrc->arfcn = bitvec_get_nth_set_bit(nbv, mrc->neigh_idx + 1);
 	mrc->bsic = (data[13] >> 1) & 0x3f;
 	if (rep->num_cell < 6)
 		return 0;
@@ -775,7 +775,7 @@
 	mrc = &rep->cell[5];
 	mrc->rxlev = ((data[13] & 0x01) << 5) | (data[14] >> 3);
 	mrc->neigh_idx = ((data[14] & 0x07) << 2) | (data[15] >> 6);
-	mrc->arfcn = bitvec_get_nth_set_bit(nbv, mrc->neigh_idx);
+	mrc->arfcn = bitvec_get_nth_set_bit(nbv, mrc->neigh_idx + 1);
 	mrc->bsic = data[15] & 0x3f;
 
 	return 0;