[PATCH 01/21] dm: core: Use const where possible in device.h

[sjg at google.com]

Update this header file to use const devices where possible, to permit
callers to also use const.

Signed-off-by: Simon Glass <sjg at chromium.org>
---

 drivers/core/device.c | 27 ++++++++++++++-------------
 include/dm/device.h   | 30 ++++++++++++++++--------------
 include/dm/read.h     |  4 ++--
 3 files changed, 32 insertions(+), 29 deletions(-)

Applied to u-boot-dm, thanks!