ahci: sata: add support for exynos5440 sata

This patch adds the compatible string of the exynos5440 sata controller
compliant with the ahci 1.3 and sata 3.0 specification.

changes in v2:
		changed the compatible string by adding the actual IP
owners name instead of the SoC vendor name.
Signed-off-by: Girish K S <ks.giri@samsung.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

drivers/ata/ahci_platform.c

@@ -327,6 +327,7 @@ static SIMPLE_DEV_PM_OPS(ahci_pm_ops, ahci_suspend, ahci_resume);
 
 static const struct of_device_id ahci_of_match[] = {
 	{ .compatible = "snps,spear-ahci", },
+	{ .compatible = "snps,exynos5440-ahci", },
 	{},
 };
 MODULE_DEVICE_TABLE(of, ahci_of_match);