- introduce new options WITH_GATLING_{ICONV,TLS,ZLIB,OPTIMIZED_CFLAGS}.
Rename the WITH_BENCHMARKS option as WITH_GATLING_BENCHMARKS for
consistency, but accept it under its old name, too.
- switch to USE_GMAKE to ease further maintenance of the port
PR: ports/82115
Submitted by: Thomas-Martin Seck <tmseck@netcologne.de> (maintainer)