phy: exynos5-usbdrd: Fix off-by-one valid value checking for args->args[0]

Current code uses args->args[0] as array subscript of phy_drd->phys[].
So the valid value range for args->args[0] is 0 ... EXYNOS5_DRDPHYS_NUM - 1.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Reviewed by: Vivek Gautam <gautam.vivek@samsung.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>

drivers/phy/phy-exynos5-usbdrd.c

diff --git a/drivers/phy/phy-exynos5-usbdrd.c b/drivers/phy/phy-exynos5-usbdrd.c
index 0437401..e2a0be7 100644
--- a/drivers/phy/phy-exynos5-usbdrd.c
+++ b/drivers/phy/phy-exynos5-usbdrd.c
@@ -531,7 +531,7 @@
 {
 	struct exynos5_usbdrd_phy *phy_drd = dev_get_drvdata(dev);
 
-	if (WARN_ON(args->args[0] > EXYNOS5_DRDPHYS_NUM))
+	if (WARN_ON(args->args[0] >= EXYNOS5_DRDPHYS_NUM))
 		return ERR_PTR(-ENODEV);
 
 	return phy_drd->phys[args->args[0]].phy;