mfd: tps65090: Add compatible string for charger subnode

This patch adds the of_compatible value for the tps65090 charger
subnode used when loading the driver to find its properties
and of_node.

Signed-off-by: Rhyland Klein <rklein@nvidia.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

drivers/mfd/tps65090.c

@@ -72,6 +72,7 @@ static struct mfd_cell tps65090s[] = {
 		.name = "tps65090-charger",
 		.num_resources = ARRAY_SIZE(charger_resources),
 		.resources = &charger_resources[0],
+		.of_compatible = "ti,tps65090-charger",
 	},
 };