Revert "usb-linux: remove unreachable default in switch statement"

This reverts commit 3c9c706c.

This breaks build (gcc 4.3.2):
    CC    usb-linux.o
 cc1: warnings being treated as errors
 /src/qemu/usb-linux.c: In function 'usb_linux_update_endp_table':
 /src/qemu/usb-linux.c:759: error: 'type' may be used uninitialized in
 this function
Reported-by: NBlue Swirl <blauwirbel@gmail.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

usb-linux.c

@@ -846,6 +846,9 @@ static int usb_linux_update_endp_table(USBHostDevice *s)
             case 0x03:
                 type = USBDEVFS_URB_TYPE_INTERRUPT;
                 break;
+            default:
+                DPRINTF("usb_host: malformed endpoint type\n");
+                type = USBDEVFS_URB_TYPE_BULK;
             }
             s->endp_table[(devep & 0xf) - 1].type = type;
             s->endp_table[(devep & 0xf) - 1].halted = 0;