This ports the following dt-utils commit (as the actual code that is changed is
removed by the preprocesser when compiling barebox this patch is only of
cosmetic nature to keep both code bases in sync):

| commit 634317c
| Author: Kim Christensen <kch@skov.dk>
| Date:   Wed Sep 18 16:48:23 2019 +0200
|
|     state: backend_bucket_circular: fix double free()
|
|     The function state_mtd_peb_read() is only a user of buf and not its owner,
|     hence it may not deallocate it.
|
|     Signed-off-by: Kim Christensen <kch@skov.dk>
|     Reviewed-by: Ulrich Ölmann <u.oelmann@pengutronix.de>
|     Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
|     Signed-off-by: Roland Hieber <rhi@pengutronix.de>

Signed-off-by: Ulrich Ölmann <u.oelmann@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>