Do not remove logging sockets. This fixes an issue where logging

sockets placed into prisons from the host environment get clobbered
by the prison's instance of cleanvar. (assuming /etc/rc is run in
the prison).

Discussed with:	pjd, green, cperciva
MFC after:	1 week

etc/rc.d/cleanvar

@@ -18,6 +18,8 @@ purgedir()
 		(
 			cd "$dir" && for file in .* *
 			do
+				# Skip over logging sockets
+				[ -S "$file" -a "$file" = "log" ] && continue
 				[ ."$file" = .. -o ."$file" = ... ] && continue
 				if [ -d "$file" -a ! -L "$file" ]
 				then