dist: stop removing /etc/systemd/system/*.mount on package uninstall

Listing /etc/systemd/system/*.mount as ghost file seems incorrect,
since user may want to keep using RAID volume / coredump directory after
uninstalling Scylla, or user may want to upgrade enterprise version.

Also, we mixed two types of files as ghost file, it should handle differently:
 1. automatically generated by postinst scriptlet
 2. generated by user invoked scylla_setup

The package should remove only 1, since 2 is generated by user decision.

However, just dropping .mount from %files section causes another
problem, rpm will remove these files during upgrade, instead of
uninstall (#8924).

To fix both problem, specify .mount files as "%ghost %config".
It will keep files both package upgrade and package remove.

See scylladb/scylla-enterprise#1780

Closes #8810
Closes #8924

Closes #8959

(cherry picked from commit f71f9786c7)

dist/debian/debian/scylla-server.postrm

@@ -12,8 +12,6 @@ case "$1" in
         if [ "$1" = "purge" ]; then
             rm -rf /etc/systemd/system/scylla-server.service.d/
         fi
-        rm -f /etc/systemd/system/var-lib-systemd-coredump.mount
-        rm -f /etc/systemd/system/var-lib-scylla.mount
         ;;
 esac
 

dist/redhat/scylla.spec

@@ -142,9 +142,9 @@ rm -rf $RPM_BUILD_ROOT
 %ghost /etc/systemd/system/scylla-server.service.d/capabilities.conf
 %ghost /etc/systemd/system/scylla-server.service.d/mounts.conf
 /etc/systemd/system/scylla-server.service.d/dependencies.conf
-%ghost /etc/systemd/system/var-lib-systemd-coredump.mount
+%ghost %config /etc/systemd/system/var-lib-systemd-coredump.mount
 %ghost /etc/systemd/system/scylla-cpupower.service
-%ghost /etc/systemd/system/var-lib-scylla.mount
+%ghost %config /etc/systemd/system/var-lib-scylla.mount
 
 %package conf
 Group:          Applications/Databases