usb: gadget: libcomposite: move composite.c into libcomposite

This moves composite.c into libcomposite and updates all gadgets.
Finally!

Acked-by: Michal Nazarewicz <mina86@mina86.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Felipe Balbi <balbi@ti.com>
diff --git a/drivers/usb/gadget/hid.c b/drivers/usb/gadget/hid.c
index 0e2e357..5fa1bfa 100644
--- a/drivers/usb/gadget/hid.c
+++ b/drivers/usb/gadget/hid.c
@@ -15,6 +15,8 @@
 #include <linux/kernel.h>
 #include <linux/platform_device.h>
 #include <linux/list.h>
+#include <linux/module.h>
+#include <linux/usb/composite.h>
 
 #include "gadget_chips.h"
 #define DRIVER_DESC		"HID Gadget"
@@ -34,9 +36,6 @@
  * the runtime footprint, and giving us at least some parts of what
  * a "gcc --combine ... part1.c part2.c part3.c ... " build would.
  */
-
-#include "composite.c"
-
 #include "f_hid.c"