usb: phy: mxs: declare variable with initialized value

Initialize vbus_value to be 0 since it's possible not to assign
any value before judgement.

Acked-by: Peter Chen <peter.chen@nxp.com
Signed-off-by: Li Jun <jun.li@nxp.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>

drivers/usb/phy/phy-mxs-usb.c

@@ -220,7 +220,7 @@ static int mxs_phy_hw_init(struct mxs_phy *mxs_phy)
 /* Return true if the vbus is there */
 static bool mxs_phy_get_vbus_status(struct mxs_phy *mxs_phy)
 {
-	unsigned int vbus_value;
+	unsigned int vbus_value = 0;
 
 	if (!mxs_phy->regmap_anatop)
 		return false;