busybox

nslookup: usee bbox network functions instead of opne-coded mess

function                                             old     new   delta
nslookup_main                                       2363    2091    -272
add_ns                                               663      65    -598
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(add/remove: 0/0 grow/shrink: 0/2 up/down: 0/-870)           Total: -870 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>