This is small CLI utility to interface with MESA IO cards for LinuxCNC.

Co-authored-by: Sandro <sandro.jaeckel@gmail.com>
Signed-off-by: wucke13 <wucke13+github@gmail.com>

This adds the LinuxCNC package. The package is quite messy, as LinuxCNC
contains a mixture of GTK, TCL, QT, Python, C and C++ programs and GUI
components.

Most notably, this package has to use an opt-in impure mechanism
for setuid wrappers (using symlinks pointing out of the store into
`/run/wrappers/bin`) as LinuxCNC itself checks if the executables
in LINUXCNC_HOME are setuid wrapped. Notably, as LINUXCNC_HOME is
also used to find assets, we can not just overwrite the environment
variable for the setuid wrapper. But the check also does not verify
$0 to have setuid, but rather `$LINUXCNC_HOME/bin/rtapi_app`.
There is an environment variable supposed to override these checks
(`LINUXCNC_FORCE_REALTIME`), but it doesn't work (upstream issue:
LinuxCNC/linuxcnc#3928)

Also, the _modern_ LinuxCNC GUI (QtDragon) uses an olt qtwebkit severed
by CVEs. As a compromise, this is an opt-in feature. Use needs to
decide for themselves whether they are willing to take the risk of the
associated CVEs.

Co-authored-by: Sandro <sandro.jaeckel@gmail.com>
Signed-off-by: wucke13 <wucke13+github@gmail.com>