unicore32-softmmu: Add puv3 ostimer support

This patch adds puv3 ostimer support, include os timer
device simulation and ptimer support in puv3 machine.

Signed-off-by: Guan Xuetao <gxt@mprc.pku.edu.cn>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
diff --git a/hw/puv3.c b/hw/puv3.c
index 2870455..5a8a27c 100644
--- a/hw/puv3.c
+++ b/hw/puv3.c
@@ -46,6 +46,9 @@
     for (i = 0; i < PUV3_IRQS_NR; i++) {
         irqs[i] = qdev_get_gpio_in(dev, i);
     }
+
+    /* Initialize minimal necessary devices for kernel booting */
+    sysbus_create_simple("puv3_ost", PUV3_OST_BASE, irqs[PUV3_IRQS_OST0]);
 }
 
 static void puv3_board_init(CPUUniCore32State *env, ram_addr_t ram_size)