busybox: nslookup: ensure unique transaction IDs for the DNS queries

busybox: nslookup: ensure unique transaction IDs for the DNS queries

On machines with a coarse monotonic clock (here: TP-Link RE200 powered
by a MediaTek MT7620A) it can happen that the two DNS requests (for A
and AAAA) share the same transaction ID. If this happens the second
reply is wrongly dropped and nslookup reports "No answer".

Fix this by ensuring that the transaction IDs are unique.

Signed-off-by: Uwe Kleine-König <uwe@kleine-koenig.org>
(cherry picked from commit 63e5ba8e69f03a584b707520db0a0821eda3024f)
Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>