udhcpc[6]: close listening socket more eagerly (e.g. across script runs)

function                                             old     new   delta
udhcpc6_main                                        2571    2600     +29
udhcpc_main                                         2588    2566     -22
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(add/remove: 0/0 grow/shrink: 1/1 up/down: 29/-22)              Total: 7 bytes

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