imx6: update gw5400-a dts

- remove common imx6q-ventana.dtsi - there isn't enough commonality to
  warrent this
- rename user led's to 1-based
- add alises used by bootloader
- clean up iomux gpios
- fix pfuze slave address
- enable sata
- add delay after release of pci reset downstream from PCIe switch
- remove PCIe clock configuration as its now handled in updated driver

Signed-off-by: Tim Harvey <tharvey@gateworks.com>
SVN-Revision: 38081