USB: <linux/usb_ch9.h> becomes <linux/usb/ch9.h>

This moves <linux/usb_ch9.h> to <linux/usb/ch9.h> to reduce some of the
clutter of usb header files.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/gadget/zero.c b/drivers/usb/gadget/zero.c
index 40710ea..ebe04e0 100644
--- a/drivers/usb/gadget/zero.c
+++ b/drivers/usb/gadget/zero.c
@@ -84,7 +84,7 @@
 #include <asm/system.h>
 #include <asm/unaligned.h>
 
-#include <linux/usb_ch9.h>
+#include <linux/usb/ch9.h>
 #include <linux/usb_gadget.h>
 
 #include "gadget_chips.h"