sama5d3xmb: update correct audio node of TWI accroding to MB revision

Default dtb is for rev.D MB. If MB version is before rev.D, we need
update the sound node's <atmel,audio-codec> property.

Signed-off-by: Josh Wu <josh.wu@atmel.com>
sama5d3x: add support in v3.10 kernel dtb sound node update

As in kernel v3.6.9 and kernel v3.10 the sound will use different
compatible string, we need to find both compatible strings so that it
can work for both v3.6.9 and v3.10 kernel.

Signed-off-by: Josh Wu <josh.wu@atmel.com>
atmel spi: fix build warning

Signed-off-by: Josh Wu <josh.wu@atmel.com>