ARM: LPC32xx: Adjust dts files to gpio dt binding

The GPIO devicetree binding in 3.5 doesn't register the various LPC32xx GPIO
banks via DT subnodes but always all at once, and changes the gpio referencing
to 3 cells (bank, gpio, flags). This patch adjusts the DTS files to this
binding that was just accepted to the gpio subsystem.

Signed-off-by: Roland Stigge <stigge@antcom.de>
Signed-off-by: Olof Johansson <olof@lixom.net>