ARM: i.MX50: fix Kindle-MX50 DT issues and warnings ...

Fix warnings generated from the kindle-mx50 dts when used in linux with W=1:
unit names should not have leading "0x"; reg property given, but no unit name;
use stdout-path instead of linux,stdout-path.
Also move the regulator-fixed node to the root node to match the convention.

Signed-off-by: Alexander Kurz <akurz@blala.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

ARM: i.MX50: Kindle-MX50 DT fixes ...

* fix IOMUX for MAX14656 IRQ, it requires a pull-up to work
* enable UART console for Model EY21
* set up IOMUX for EY21 GPIO lid-close hall sensor
* remove IOMUX for non-existing EY21 GPIO keys
* replace space indention with tabs

Signed-off-by: Alexander Kurz <akurz@blala.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

ARM: i.MX50: Amazon Kindle: Model EY21 compatibility check ...

Extend the compatibility check for i.MX50 based kindles also on model EY21.

Signed-off-by: Alexander Kurz <akurz@blala.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

ARM: i.MX50: Add support for i.MX50 based Amazon Kindle e-book readers ...

The Kindle Model No. D01100 (Kindle Wi-Fi), D01200 (Kindle Touch)
and EY21 (Kindle Paperwhite) are refered as the Kindle 4th and 5th generation.
Those models are based on an i.MX50 SoC and use LPDDR1 or LPDDR2 Memory.

The devices boot in internal boot mode from a build-in eMMC, alternatively
some devices may be set into USB-downloader mode by pressing a specific key
at startup.

Add support for the i.MX50 based Kindle device and make barebox a drop-in
replacement for the factory shipped u-boot image.

Notable features:
- Support for eMMC, USB, UART, I2C, SPI and Keys (except keyboard).
- LPDDR1 and LPDDR2 setup is done via DCD, the same imximage may be used
  for USB-startup and for installation.
- Support for vendor specific ATAGs that are required for the Kindle-System.
- usbserial barebox console access by pressing Select button at startup,
  alternatively full console support on connector J14.

Signed-off-by: Alexander Kurz <akurz@blala.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>