staging/lustre/lnet: Fix potential uninitialized variable warning

Greg reports that with one of the patches in his queue
there's now an unused variable warning in lnet_parse_ip2nets
for ipaddrs variable.
Apparently the warning is a false positive as in all cases where
lnet_ipaddr_enumerate can return without setting ipaddrs to something
a negative return value is returned that is then checked
before we actually use ipaddrs.

Assign ipaddrs to NULL to quiet this.
Signed-off-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/lustre/lnet/lnet/config.c

@@ -1172,7 +1172,7 @@ lnet_ipaddr_enumerate(__u32 **ipaddrsp)
 int
 lnet_parse_ip2nets(char **networksp, char *ip2nets)
 {
-	__u32     *ipaddrs;
+	__u32     *ipaddrs = NULL;
 	int	nip = lnet_ipaddr_enumerate(&ipaddrs);
 	int	rc;