arm: exynos: Add base support for 5422

Add base support for exynos5422 SoC, this soc is pin to pin compatible
with exynos5420. This patch also does the neccessary change needed to support
exynos5422 core functionality like pmu, pm and bL.

BUG=chrome-os-partner:24687
TEST=Build and booted on pi

Signed-off-by: Alim Akhtar <alim.akhtar@samsung.com>

Change-Id: I5b2f6fca9f6e927bee419eea0a2812e0afc1c48b
Reviewed-on: https://chromium-review.googlesource.com/181343
Tested-by: Alim Akhtar <alim.akhtar@samsung.com>
Reviewed-by: Doug Anderson <dianders@chromium.org>
Commit-Queue: Doug Anderson <dianders@chromium.org>
ARM: EXYNOS: Change the base address values for zreladdr-y,params_phys-y
from 40000000 to 20000000

This patch is temporarily to boot.
i2c: exynos5: Clock_disable_unprepare comment temporarily
ARM: Add Kconfig to 16 of NR_BANKS for EXYNOS5420
ARM: dts: Add Initial device tree support for odroidxu2

Add initial device tree for odroidxu2
ARM: odroidxu2_defconfig: odroidxu2 board based on exynos5420
 ARM: dts: odroid-xu2: Add heartbead and mmc LEDs support

 Add the support for LED1 on ODROID-XU2 board.
 -Blue LED will be used for heartbeat
 -Green LED will be used for eMMC
 -Red LED will be used for microSD
ARM: odroidxu2_defconfig: Disable CONFIG_SECURITY_CHROMIUMOS
ARM: dts: Add dp_hpd properties for DP on odroid-xu2
 ARM: dts: Add ldo28 in regulaors node for DP on odroid-xu2
ARM: dts: odroid-xu2: Add timing for AOC 22" on lcd_dp0
ARM: dts: odroid-xu2: Set HS-Tx Pre-emphasis rate for usb3phy to 1X

Setting a Pre-emphasis current control of 1X, which increases
the Pre-emphasis current from current value of 0uA to 600uA.
This helps us in meeting USB compliance
arm: dts: odroid-xu2: Enable internal FIMD dithering logic

Add DT properties to specify RDithpos, GDithpos and BDithpos
values and enable the internal dithering logic of FIMD.
ARM: dts: Add non-removable property at emmc for odroid-xu2