staging/usbip: add uapi header to export usbip kernel interfaces

usbip userspace has duplicated enum definition to report usbip device
status maintained by the kernel. Adding an usbip uapi header file will
define the kernel - userspace interface for this device status. This
new uapi file is added under usbip/uapi to keep the staging tree code
self-contained. When usbip moves to mainline drivers, this file should
be moved under uapi/linux
Signed-off-by: Shuah Khan <shuah.kh@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/usbip/uapi/usbip.h

+/*
+ *	usbip.h
+ *
+ *	USBIP uapi defines and function prototypes etc.
+*/
+
+#ifndef _UAPI_LINUX_USBIP_H
+#define _UAPI_LINUX_USBIP_H
+
+/* usbip device status - exported in usbip device sysfs status */
+enum usbip_device_status {
+	/* sdev is available. */
+	SDEV_ST_AVAILABLE = 0x01,
+	/* sdev is now used. */
+	SDEV_ST_USED,
+	/* sdev is unusable because of a fatal error. */
+	SDEV_ST_ERROR,
+
+	/* vdev does not connect a remote device. */
+	VDEV_ST_NULL,
+	/* vdev is used, but the USB address is not assigned yet */
+	VDEV_ST_NOTASSIGNED,
+	VDEV_ST_USED,
+	VDEV_ST_ERROR
+};
+#endif /* _UAPI_LINUX_USBIP_H */