mfd: ab8500-core: Apply the AB8500 CODEC's compatible string to its MFD cell

Provide a compatible string for the AB8500 CODEC to aid in
configuration property look-up from its associated Device Tree
node.

Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

drivers/mfd/ab8500-core.c

@@ -1076,6 +1076,7 @@ static struct mfd_cell __devinitdata ab8500_devs[] = {
 	},
 	{
 		.name = "ab8500-codec",
+		.of_compatible = "stericsson,ab8500-codec",
 	},
 };