ARM: configs: at91: sama5: enable SAMA5D2_PIOBU

Driver is enabled as a module.

Signed-off-by: Razvan Stefanescu <razvan.stefanescu@microchip.com>
Link: https://lore.kernel.org/r/20200325102223.24827-1-eugen.hristev@microchip.com


Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>