games/doomlegacy: update Doom Legacy to version 1.48.14 (rev1663)

• Retire IPX support (removed from FreeBSD nearly 10 years ago)
• Add optional support for zipped WAD files, e.g. `phobiata.zip'
• Link against zlib to decompress some "extended node" formats
• Do not patch the `make_options' file, propagate the variables down to make(1) via the environment and command line instead
• Drop needless parentheses when installing documentation files

Reported by: portscout