usb: phy: fix return value check of usb_get_phy

usb_get_phy will return -ENODEV if it's not able to find the phy. Hence
fixed all the callers of usb_get_phy to check for this error condition
instead of relying on a non-zero value as success condition.

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
diff --git a/drivers/usb/musb/da8xx.c b/drivers/usb/musb/da8xx.c
index d731c80..0f9fcec 100644
--- a/drivers/usb/musb/da8xx.c
+++ b/drivers/usb/musb/da8xx.c
@@ -29,6 +29,7 @@
 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/clk.h>
+#include <linux/err.h>
 #include <linux/io.h>
 #include <linux/platform_device.h>
 #include <linux/dma-mapping.h>
@@ -426,7 +427,7 @@
 
 	usb_nop_xceiv_register();
 	musb->xceiv = usb_get_phy(USB_PHY_TYPE_USB2);
-	if (!musb->xceiv)
+	if (IS_ERR_OR_NULL(musb->xceiv))
 		goto fail;
 
 	if (is_host_enabled(musb))