bootchartd: warn if .config looks wrong

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
init: fix illegal memory access when max message length is reached

Signed-off-by: Yuan-Hsiang Lee <yhlee@ubnt.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
udhcpc: allow zero server-id. Closes 6614.

function                                             old     new   delta
bcast_or_ucast                                         -      47     +47
udhcp_send_kernel_packet                             271     295     +24
udhcpc_main                                         2696    2705      +9
udhcp_send_raw_packet                                456     459      +3
send_release                                          90      76     -14
send_renew                                           105      77     -28
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(add/remove: 1/0 grow/shrink: 3/2 up/down: 83/-42)             Total: 41 bytes

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