SYSTEMD: remove unused CAP_KILL

There are some known issues like SSSD#5536 but those have to be
solved differently. Having 'CAP_KILL' in sssd.service doesn't
help anyway (and currently isn't used anyhow).

src/sysv/systemd/sssd.service.in

@@ -17,7 +17,7 @@ PIDFile=@pidpath@/sssd.pid
 # Currently main SSSD process ('sssd') always runs under 'root'
 # ('User=' and 'Group=' defaults to 'root' for system services)
 # 'CapabilityBoundingSet' is used to limit privileges set:
-CapabilityBoundingSet= @additional_caps@ CAP_KILL CAP_SETGID CAP_SETUID
+CapabilityBoundingSet= @additional_caps@ CAP_SETGID CAP_SETUID
 Restart=on-abnormal
 @supplementary_groups@