[th/nm-updown-split] contrib/rpm: split ifup/ifdown compat scripts to new package NetworkManager-initscripts-updown
Previously (on RHEL<=8 and Fedora<=35), NetworkManager package contains the compat scripts nm-ifup/nm-ifdown.
If initscripts package (not network-scripts!) is installed, then a RPM trigger links them as alternatives for the ifup/ifdown commands.
One problem is that dnf provides /usr/sbin/ifup lists the
NetworkManager package. Which is technically true, but on RHEL9 where
initscripts is not installed by default, dnf install NetworkManager
does not actually create those scripts.
Solve that by moving those scripts to a new subpackage NetworkManager-initscripts-updown. This package will now be suggested as containing the ifup/ifdown scripts, and as the package depends on "initscripts", the RPM trigger will always create the alternatives.
The name "initscripts-updown" is chosen because in the future we might have additonal initscripts/ifcfg related subpackages to contain the ifcfg-rh plugin (NetworkManager-initscripts-ifcfg) or ifcfg-rh migration tools (NetworkManager-initscripts-tools).