udhcp: code shrink

function                                             old     new   delta
attach_option                                          -     380    +380
read_opt                                             859     443    -416
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(add/remove: 1/0 grow/shrink: 0/1 up/down: 380/-416)          Total: -36 bytes

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