[PATCH -next] usb: dwc3: include extcon.h to fix compile error

[Guan Jing]

If dwc3 is not include extcon.h, the dwc3 driver
will fail to link:

drivers/usb/dwc3/core.o: In function `dwc3_probe':
core.c:(.text+0x1095): undefined reference to `extcon_get_edev_by_phandle'
core.c:(.text+0x10bd): undefined reference to `extcon_get_extcon_dev'

Add miss #include <linux/extcon.h> to fix this error.

Reported-by: Hulk Robot <hulkci@xxxxxxxxxx>
Signed-off-by: Guan Jing <guanjing6@xxxxxxxxxx>
---
 drivers/usb/dwc3/core.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index 950e238c65bf..ea7259443283 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -33,6 +33,7 @@
 #include <linux/usb/gadget.h>
 #include <linux/usb/of.h>
 #include <linux/usb/otg.h>
+#include <linux/extcon.h>
 
 #include "core.h"
 #include "gadget.h"
-- 
2.17.1