USB: omap_udc: fix omap_udc_start() on 15xx machines

BugLink: https://bugs.launchpad.net/bugs/1811080

[ Upstream commit 6ca6695f ]

On OMAP 15xx machines there are no transceivers, and omap_udc_start()
always fails as it forgot to adjust the default return value.
Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Juerg Haefliger <juergh@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>

drivers/usb/gadget/udc/omap_udc.c

@@ -2045,7 +2045,7 @@ static inline int machine_without_vbus_sense(void)
 static int omap_udc_start(struct usb_gadget *g,
 		struct usb_gadget_driver *driver)
 {
-	int		status = -ENODEV;
+	int		status;
 	struct omap_ep	*ep;
 	unsigned long	flags;
 
@@ -2083,6 +2083,7 @@ static int omap_udc_start(struct usb_gadget *g,
 			goto done;
 		}
 	} else {
+		status = 0;
 		if (can_pullup(udc))
 			pullup_enable(udc);
 		else