build: No longer need to hack the PATH variable in config.site

Now all of the tools have well-defined absolute paths to them.

depends/config.site.in

@@ -78,7 +78,6 @@ if test "@host_os@" = darwin; then
   BREW=no
 fi
 
-PATH="${depends_prefix}/native/bin:${PATH}"
 PKG_CONFIG="$(which pkg-config) --static"
 
 # These two need to remain exported because pkg-config does not see them