update network service examples

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

examples/var_service/dhcp_if/log/run

@@ -6,7 +6,7 @@ logdir="/var/log/service/`(cd ..;basename $PWD)`"
 mkdir -p "$logdir" 2>/dev/null
 chown -R "$user": "$logdir"
 chmod -R go-rwxst,u+rwX "$logdir"
-rm logdir
+rm -rf logdir
 ln -s "$logdir" logdir
 
 # make this dir accessible to logger