also revert the part which appempted to "fix" that in client
function old new delta
udhcpd_main 1949 1964 +15
send_renew 142 105 -37
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(add/remove: 0/0 grow/shrink: 1/1 up/down: 15/-37) Total: -22 bytes
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>