[PATCH] dhclient link timeout option

Hello,

I've noticed that when I have both my wired and wireless interfaces on
my laptop enabled with DHCP,
it is always started on boot, but if there is no cable plugged or
known wifi ap, dhclient waits for 10 seconds
for link for each interface and thus delaying the boot process by 20
seconds. (background_dhclient didn't help).
So I've decided to add a link timeout option to dhclient to specify
how long it should wait for link on startup,
which seems to work pretty nicely in my setup. I hope others might
find this useful too.

Regards,
Niki