Fix unaligned access found by addr. sanitizer

gprs_bssgp.c:461:9: runtime error: load of misaligned address
0x62100001a66b for type 'uint32_t', which requires 4 byte alignment

gprs_ns.c:937:16: runtime error: load of misaligned address
0x61d00002a97f for type 'uint16_t', which requires 2 byte alignment
diff --git a/src/gb/gprs_ns.c b/src/gb/gprs_ns.c
index a29c946..6879c70 100644
--- a/src/gb/gprs_ns.c
+++ b/src/gb/gprs_ns.c
@@ -934,8 +934,8 @@
 		return -EINVAL;
 	}
 
-	nsvci = ntohs(*(uint16_t *) TLVP_VAL(&tp, NS_IE_VCI));
-	nsei  = ntohs(*(uint16_t *) TLVP_VAL(&tp, NS_IE_NSEI));
+	nsvci = ntohs(tlvp_val16_unal(&tp, NS_IE_VCI));
+	nsei  = ntohs(tlvp_val16_unal(&tp, NS_IE_NSEI));
 
 	LOGP(DNS, LOGL_INFO, "NSVCI=%u%s Rx NS RESET ACK (NSEI=%u, NSVCI=%u)\n",
 	     (*nsvc)->nsvci, (*nsvc)->nsvci_is_valid ? "" : "(invalid)",