remove unused PesHeader

clears build warning:
unused variable 'fragment_header'

Change-Id: I4b8eee43dad441e2cc87419b2964118fb39330b4
diff --git a/m2ts/vpxpes_parser.cc b/m2ts/vpxpes_parser.cc
index cc12ec3..4f6fe5c 100644
--- a/m2ts/vpxpes_parser.cc
+++ b/m2ts/vpxpes_parser.cc
@@ -261,7 +261,6 @@
 
 bool VpxPesParser::AccumulateFragmentedPayload(std::size_t pes_packet_length,
                                                std::size_t payload_length) {
-  PesHeader fragment_header;
   const std::size_t first_fragment_length =
       pes_packet_length - kPesOptionalHeaderSize - kBcmvHeaderSize;
   for (std::size_t i = 0; i < first_fragment_length; ++i) {