This ports the following barebox commit:

| commit b6a3532
| Author: Juergen Borleis <jbe@pengutronix.de>
| Date:   Tue Aug 15 15:46:35 2017 +0200
|
|     state: add debugging help
|
|     While working on the state documentation it turns out to be helpful to have
|     more debug messages while a developer implements a 'state' variable set
|     and tries to configure it correctly.
|
|     Signed-off-by: Juergen Borleis <jbe@pengutronix.de>
|     Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

Signed-off-by: Ulrich Ölmann <u.oelmann@pengutronix.de>
Signed-off-by: Roland Hieber <rhi@pengutronix.de>