ARM: dts: exynos5: Use existing constants for GPIOs

Use standard GPIO constants to enhance the readablility of DT GPIOs.
ARM: dts: exynos5: Include IRQ header

Some nodes in EXYNOS5 DTs now use edge or level sensitive interrupts.
ARM: dts: odroid-xu: Add heartbead and mmc LEDs support

Add the support for LED1 on ODROID-XU board.
-Red LED will be used for heartbeat
-Green LED will be used for eMMC
-Blue LED will be used for microSD