oldnet: convert netmask to decimal numbers in _netmask2cidr

Free BSD's ifconfig outputs a netmask in the form 0xffffff00, which
was translating to 0xff.0xff.0xff.0x00,. Now we convert this to decimal
numbers before we convert it to cidr notation.

Reported-by: 4glitch@gmail.com
X-Gentoo-Bug: 460268
X-Gentoo-Bug-URL: https://bugs.gentoo.org/show_bug.cgi?id=460268

init.d/net.lo.in

@@ -151,6 +151,9 @@ _netmask2cidr()
 	local i= len=
 	local IFS=.
 	for i in $1; do
+		case $i in
+			0x*)	i=$((i)) ;;
+		esac
 		while [ ${i} -ne 0 ]; do
 			: $(( len += i % 2 ))
 			: $(( i >>= 1 ))