Ports: Remove the separate branch for extracting .tar.gz files

This can just use the default `tar` invocation, which successfully
recognizes the type automatically. In fact, `.tar.gz` and `.tgz` are
already listed by that particular case anyways.

Ports/.port_include.sh

@@ -364,10 +364,6 @@ fetch() {
 
  if [ ! -f "$workdir"/.${filename}_extracted ]; then
  case "$filename" in
- *.tar.gz|*.tgz)
- run_nocd tar -xzf "${PORT_META_DIR}/${filename}"
- run touch .${filename}_extracted
- ;;
  *.tar.gz|*.tar.bz|*.tar.bz2|*.tar.xz|*.tar.lz|*.tar.zst|.tbz*|*.txz|*.tgz)
  run_nocd tar -xf "${PORT_META_DIR}/${filename}"
  run touch .${filename}_extracted