usb: composite: Move bitmap related operations to ./include/linux/bitmap.h

The BITMAP related operations can now be moved to ./include/linux/bitmap.h
file to mimic the Linux kernel directory tree.

This change also allows to remove the lin_gadget_compat.h header file
(which is a legacy code only for composite U-boot layer).
It was also possible to remove #includes from several USB gadget drivers.

Signed-off-by: Lukasz Majewski <lukma@denx.de>
Reviewed-by: Stefan Agner <stefan.agner@toradex.com>

include/linux/types.h

@@ -158,4 +158,7 @@ struct ustat {
 	char			f_fpack[6];
 };
 
+#define DECLARE_BITMAP(name, bits) \
+	unsigned long name[BITS_TO_LONGS(bits)]
+
 #endif /* _LINUX_TYPES_H */