init.d/net-online: pass -n to ping to avoid rDNS overhead

e21b01b fixed one of the issues mentioned
in Gentoo bug #650584 but not the other one. `ping` without `-n` will perform
reverse DNS lookups for IPs which we don't want, as it introduces a delay
and confuses the calculation we make.

Bug: https://bugs.gentoo.org/650584
Bug: #353

Author: thesamesam

init.d/net-online.in

@@ -66,7 +66,7 @@ start ()
  	ping_test_host="${ping_test_host:-google.com}"
  	if [ -n "$ping_test_host" ]; then
 		while $infinite || [ $timeout -gt 0 ]; do
-			ping -c 1 $ping_test_host > /dev/null 2>&1
+			ping -n -c 1 $ping_test_host > /dev/null 2>&1
 			rc=$?
 			[ $rc -eq 0 ] && break
 			sleep 1