Some Logging Cleanup (#810)

* Remove unnecessary WPP definition.
* Various other small fixes.

src/core/net/ip6.cpp

@@ -31,6 +31,8 @@
  *   This file implements IPv6 networking.
  */
 
+#define WPP_NAME "ip6.tmh"
+
 #include <common/code_utils.hpp>
 #include <common/debug.hpp>
 #include <common/logging.hpp>
@@ -430,6 +432,8 @@ ThreadError Ip6::HandleDatagram(Message &message, Netif *netif, int8_t interface
     uint8_t nextHeader;
     uint8_t hopLimit;
 
+    otLogFuncEntry();
+
 #if 0
     uint8_t buf[1024];
     message.Read(0, sizeof(buf), buf);
@@ -533,6 +537,7 @@ exit:
         message.Free();
     }
 
+    otLogFuncExitErr(error);
     return error;
 }
 
@@ -542,6 +547,8 @@ ThreadError Ip6::ForwardMessage(Message &message, MessageInfo &messageInfo, uint
     int8_t interfaceId;
     Netif *netif;
 
+    otLogFuncEntry();
+
     if (messageInfo.GetSockAddr().IsMulticast())
     {
         // multicast
@@ -590,6 +597,8 @@ ThreadError Ip6::ForwardMessage(Message &message, MessageInfo &messageInfo, uint
     SuccessOrExit(error = netif->SendMessage(message));
 
 exit:
+
+    otLogFuncExitErr(error);
     return error;
 }