[ATM]: Suppress some sparse warnings

  CHECK   net/atm/br2684.c
net/atm/br2684.c:665:13: warning: context imbalance in 'br2684_seq_start' - wrong count at exit
net/atm/br2684.c:676:13: warning: context imbalance in 'br2684_seq_stop' - unexpected unlock
  CHECK   net/atm/lec.c
net/atm/lec.c:196:23: warning: expensive signed divide
  CHECK   net/atm/proc.c
net/atm/proc.c:151:14: warning: context imbalance in 'vcc_seq_start' - wrong count at exit
net/atm/proc.c:154:13: warning: context imbalance in 'vcc_seq_stop' - unexpected unlock

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/atm/lec.c b/net/atm/lec.c
index 0a9c4261..1a8c4c6 100644
--- a/net/atm/lec.c
+++ b/net/atm/lec.c
@@ -176,7 +176,7 @@
 static unsigned char *get_tr_dst(unsigned char *packet, unsigned char *rdesc)
 {
 	struct trh_hdr *trh;
-	int riflen, num_rdsc;
+	unsigned int riflen, num_rdsc;
 
 	trh = (struct trh_hdr *)packet;
 	if (trh->daddr[0] & (uint8_t) 0x80)