remove comment about wire_format_lite_inl.h
remove comment about wire_format_lite_inl.h

The wire_format_lite_inl.h header file was made unnecessary in #5839
and deleted in #5921, so remove the comment about it.
google/protobuf,google/protobuf,google/protobuf,google/protobuf,google/protobuf,google/protobuf,google/protobuf,google/protobuf,google/protobuf,google/protobuf,google/protobuf