lib/string: add strcat function

for future to acquire the dt filename.

Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
OneWire: Add get cpu module board id.

also rearrange the code.

Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
sdcard: dynamically achieve the dt filename from the OneWire information

for at91sam9x5ek: g15(_pda).dtb, g25(_pda).dtb, g35(_pda).dtb, x25(_pda).dtb, x35(_pda).dtb,
for sama5d3xek: d31(_pda).dtb, d33(_pda).dtb, d34(_pda).dtb, d35(_pda).dtb

Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
android4sam: add default conf for booting Android

Add default configuration file for booting Android
  - eknf: ek board boot from NAND flash
  - eksd: ek board boot from SD card
  - pdanf: ek with PDA panel boot from NAND flash
  - pdasd: ek with PDA panel boot from SD card

Signed-off-by: Bo Shen <voice.shen@atmel.com>