tcp: fix outsegs stat for TSO segments

Account for TSO segments of an skb in TCP_MIB_OUTSEGS counter.  Without
doing this, the counter can be off by orders of magnitude from the
actual number of segments sent.

Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/snmp.h b/include/net/snmp.h
index 884fdbb..92456f1 100644
--- a/include/net/snmp.h
+++ b/include/net/snmp.h
@@ -133,6 +133,8 @@
 			__this_cpu_add(mib[0]->mibs[field], addend)
 #define SNMP_ADD_STATS_USER(mib, field, addend)	\
 			this_cpu_add(mib[1]->mibs[field], addend)
+#define SNMP_ADD_STATS(mib, field, addend)	\
+			this_cpu_add(mib[0]->mibs[field], addend)
 /*
  * Use "__typeof__(*mib[0]) *ptr" instead of "__typeof__(mib[0]) ptr"
  * to make @ptr a non-percpu pointer.