extcon: standard cable names definition and declaration changed

With this change now individual drivers can use standard cable
names as below:
static const char *arizona_cable[] = {
    extcon_cable_name[EXTCON_USB],
    extcon_cable_name[EXTCON_USB_HOST],
    "CUSTOM_CABLE"
    NULL,
}

Signed-off-by: anish kumar <anish198519851985@gmail.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
diff --git a/include/linux/extcon.h b/include/linux/extcon.h
index 7443a56..2c26c14 100644
--- a/include/linux/extcon.h
+++ b/include/linux/extcon.h
@@ -68,7 +68,7 @@
 	EXTCON_VIDEO_OUT,
 	EXTCON_MECHANICAL,
 };
-extern const char *extcon_cable_name[];
+extern const char extcon_cable_name[][CABLE_NAME_MAX + 1];
 
 struct extcon_cable;