i2c: at91: print hardware version

The probe() function now prints the hardware version of the I2C
controller.

Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com>
[wsa: s/version/hw version/] for clarity]
Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>