ARM: LPC32xx: Add dt settings to the at25 node

Add the reg, cs-gpios and max-frequencies that are needed for spi
device registry in phy3250.
Adds also the pl022 internal transfers details via dt

Signed-off-by: Alexandre Pereira da Silva <aletes.xgr@gmail.com>
Signed-off-by: Roland Stigge <stigge@antcom.de>