Delete unused code

The "hostname" and "port" variables defined in "transport_common.cc"
at line 98 were unused and they are triggering compiler warnings
under the latest clang. This patch removes them.

Change-Id: I3c201c1640fa26feeca1dd81b3e439b3cf861a2a
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/100147
Reviewed-by: David Benjamin <davidben@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
Auto-Submit: Haowei Wu <haowei@google.com>
Commit-Queue: Haowei Wu <haowei@google.com>

tool/transport_common.cc

diff --git a/tool/transport_common.cc b/tool/transport_common.cc
index 8e4c164..dc564cf 100644
--- a/tool/transport_common.cc
+++ b/tool/transport_common.cc
@@ -95,7 +95,6 @@
                           const std::string &hostname_and_port) {
   size_t colon_offset = hostname_and_port.find_last_of(':');
   const size_t bracket_offset = hostname_and_port.find_last_of(']');
-  std::string hostname, port;
 
   // An IPv6 literal may have colons internally, guarded by square brackets.
   if (bracket_offset != std::string::npos &&