Delay after hub power on up to 10 seconds.

This is a workaround for usb sticks which are slow to respond.

DO NOT SUBMIT.

Change-Id: I4f86a3a273138675731ebdd90f4ddf977a8e0877
Switch default device tree to spring

Signed-off-by: Andreas Färber <andreas.faerber@web.de>
Fix vboot CPPFLAGS

Signed-off-by: Andreas Färber <andreas.faerber@web.de>
Fix device tree syntax

Inline PERIPH_ID_* definitions.

Signed-off-by: Andreas Färber <andreas.faerber@web.de>
Adapt default boot options for USB boot

Signed-off-by: Andreas Färber <andreas.faerber@web.de>