char/cadence_uart: Mark struct fields as public/private

As per current QOM conventions.
Signed-off-by: NPeter Crosthwaite <peter.crosthwaite@xilinx.com>
Message-id: a1e31bd62e9709ffb9b3efc6c120f83f30b7a660.1388626249.git.peter.crosthwaite@xilinx.com
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

hw/char/cadence_uart.c

@@ -110,7 +110,9 @@
 #define CADENCE_UART(obj) OBJECT_CHECK(UartState, (obj), TYPE_CADENCE_UART)
 
 typedef struct {
+    /*< private >*/
     SysBusDevice parent_obj;
+    /*< public >*/
 
     MemoryRegion iomem;
     uint32_t r[R_MAX];