Android-Clatd: Remove unused variable

For build-system CFLAGS clean-up, fix unused-but-set variables.

Change-Id: I3fc6b0d9bec87cd54d7b5199108cff576b4be677
diff --git a/clatd_test.cpp b/clatd_test.cpp
index 9a09b48..b61da9f 100644
--- a/clatd_test.cpp
+++ b/clatd_test.cpp
@@ -431,7 +431,6 @@
   if (socketpair(AF_UNIX, SOCK_DGRAM | SOCK_NONBLOCK, 0, fds)) {
     abort();
   }
-  struct tun_pi tun_header = { 0, 0 };
 
   char foo[512];
   snprintf(foo, sizeof(foo), "%s: Invalid original packet", msg);
@@ -442,13 +441,11 @@
   int version = ip_version(original);
   switch (version) {
     case 4:
-      tun_header.proto = htons(ETH_P_IP);
       expected_proto = htons(ETH_P_IPV6);
       read_fd = fds[1];
       write_fd = fds[0];
       break;
     case 6:
-      tun_header.proto = htons(ETH_P_IPV6);
       expected_proto = htons(ETH_P_IP);
       read_fd = fds[0];
       write_fd = fds[1];