Do not parse the FC_TEMPLATEDIR if user has own configuration paths
This additional FcConfigParseOnly call has been added in 9a0fcb94 unconditionally. I think this was an oversight, since other parts of code pay attention to not read into system directories if user has own configuration.
Users who are overriding FONTCONFIG_PATH or FONTCONFIG_FILE has to pay attention themselves to provide a cache directory, and if not, the code will still add the xdg or system one for them.
On the other hand, reading into the system even if the environment variables are present, is very inconvenient for powerusers, who try to understand and customize fontconfig in their HOME and during debugging (strace, gdb) can be a very inconvenient red-herring trying to understand why FC_TEMPLATEDIR is opened at all.