debian: Avoid logrotate error if /var/run/openvswitch does not exist.

Signed-off-by: Alfredo Finelli <alf@computationes.de>
Signed-off-by: Ben Pfaff <blp@nicira.com>

Author: Alfredo Finelli

AUTHORS

@@ -6,6 +6,7 @@ Alexandru Copot         alex.mihai.c@gmail.com
 Alexei Starovoitov      ast@plumgrid.com
 Alexey I. Froloff       raorn@altlinux.org
 Alex Wang               alexw@nicira.com
+Alfredo Finelli         alf@computationes.de
 Andrew Evans            aevans@nicira.com
 Andrew Lambeth          wal@nicira.com
 Andy Hill               hillad@gmail.com

debian/openvswitch-switch.logrotate

@@ -7,8 +7,10 @@
     rotate 30
     postrotate
     # Tell Open vSwitch daemons to reopen their log files
-    for pidfile in `cd /var/run/openvswitch && echo *.pid`; do
-        ovs-appctl -t "${pidfile%%.pid}" vlog/reopen
-    done
+    if [ -d /var/run/openvswitch ]; then
+        for pidfile in `cd /var/run/openvswitch && echo *.pid`; do
+            ovs-appctl -t "${pidfile%%.pid}" vlog/reopen
+        done
+    fi
     endscript
 }