ARM: dts: imx6: Add Savageboard common file

* Memory
  memblock for DDR3 1GB

* Regulator
  3.3V for panel and backlight.

* Display
  Enable HDMI and LVDS panel. Savageboard supports AVIC TM097TDH02 panel
  which is compatible with Hannstar HSD100PXN1, so reuse it.

* Clock
  The commit d28be499 ("ARM: dts: imx6qdl-sabresd: Allow HDMI and
  LVDS to work simultaneously") is applied to support LVDS and HDMI output
  at the same time.

* Pinmux
  Support eMMC, ethernet, gpio key for power button, I2C, PWM, SD card
  and UART.

* Others
  Enable ethernet, UART1 debug, USB host, USDHC3 for microSD card and
  USDHC4 for built-in eMMC storage.

Reviewed-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Milo Kim <woogyom.kim@gmail.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>