dts: flash: w25qxxdv: Add Device Tree Support for SPI FLASH w25qxxdv

Convert the w25qxxdv driver to use device tree for SPI device params.
Updated the Arduino 101 config to use device tree to specify the SPI
flash.  Update the arduino_101_sss to drop Kconfig support for the
w25qxxdv flash.

Signed-off-by: Kumar Gala <kumar.gala@linaro.org>