ipconfig: Only bootp paths should reference ic_dev_xid.

It is only tested, and declared, in the bootp code.

So, in ic_dynamic() guard it's setting with IPCONFIG_BOOTP.

Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/ipconfig.c b/net/ipv4/ipconfig.c
index f02f594..5bbef4f 100644
--- a/net/ipv4/ipconfig.c
+++ b/net/ipv4/ipconfig.c
@@ -1217,10 +1217,10 @@
 	get_random_bytes(&timeout, sizeof(timeout));
 	timeout = CONF_BASE_TIMEOUT + (timeout % (unsigned int) CONF_TIMEOUT_RANDOM);
 	for (;;) {
+#ifdef IPCONFIG_BOOTP
 		/* Track the device we are configuring */
 		ic_dev_xid = d->xid;
 
-#ifdef IPCONFIG_BOOTP
 		if (do_bootp && (d->able & IC_BOOTP))
 			ic_bootp_send_if(d, jiffies - start_jiffies);
 #endif