usb: class specific interface requests

Mass Storage Reset and Get Max LUN are class specific requests, but
they were not marked as such in hw/usb-msd.c, moved therefore
ClassInterfaceRequest and ClassInterfaceOutRequest from hw/usb-net.c
to hw/usb.h.
Furthermore there was a problem in hw/usb-ohci.c when using DEBUG
concerning systems where size_t is a 32 bit integer (printf resulted
in a segmentation fault).

Signed-off-by: Max Reitz <max@tyndur.org>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
diff --git a/hw/usb-msd.c b/hw/usb-msd.c
index e9235ea..c1c2537 100644
--- a/hw/usb-msd.c
+++ b/hw/usb-msd.c
@@ -327,14 +327,12 @@
         ret = 0;
         break;
         /* Class specific requests.  */
-    case (((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8) | MassStorageReset):
-    case MassStorageReset:
+    case ClassInterfaceOutRequest | MassStorageReset:
         /* Reset state ready for the next CBW.  */
         s->mode = USB_MSDM_CBW;
         ret = 0;
         break;
-    case (((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8) | GetMaxLun):
-    case GetMaxLun:
+    case ClassInterfaceRequest | GetMaxLun:
         data[0] = 0;
         ret = 1;
         break;