Add the support of AC97 on the at91sam9rl chip and -ek board.
It will share the code with AVR32 ac97c alsa driver "atmel_ac97c".
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com> Acked-by: Andrew Victor <linux@maxim.org.za> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>