build: fix systemd-journal-upload installation Fixes: $ ./configure ... --disable-microhttpd --enable-libcurl --enable-sysusers $ make && make install DESTDIR=$(pwd)/INST $ ls INST/usr/lib/sysusers.d/ basic.conf systemd.conf There is no a file with `systemd-journald-upload`

build-sys: configure the list of system users, files and directories Choose which system users defined in sysusers.d/systemd.conf and files or directories in tmpfiles.d/systemd.conf, should be provided depending on comile-time configuration.

sysusers: split up default sysusers snippet This ways, distributions have an easier way to replace the OS specific generic groups/users while keeping systemd's own.

sysusers: hide generate .conf file