Makefile: remove .wad.gz target
Makefile: remove .wad.gz target

This is probably not something that anybody uses... either "make dist"
or custom scripts outside of the Makefile to generate Zip files are
often used.

jmtd/freedoom,jmtd/freedoom,jmtd/freedoom,CWolfRU/freedoom,CWolfRU/freedoom