qdev: rework device properties.

This patch is a major overhaul of the device properties.  The properties
are saved directly in the device state struct now, the linked list of
property values is gone.

Advantages:
  * We don't have to maintain the list with the property values.
  * The value in the property list and the value actually used by
    the device can't go out of sync any more (used to happen for
    the pci.devfn == -1 case) because there is only one place where
    the value is stored.
  * A record describing the property is required now, you can't set
    random properties any more.

There are bus-specific and device-specific properties.  The former
should be used for properties common to all bus drivers.  Typical
use case is bus addressing, i.e. pci.devfn and i2c.address.

Properties have a PropertyInfo struct attached with name, size and
function pointers to parse and print properties.  A few common property
types have PropertyInfos defined in qdev-properties.c.  Drivers are free
to implement their own very special property parsers if needed.

Properties can have default values.  If unset they are zero-filled.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
diff --git a/hw/esp.c b/hw/esp.c
index 88d42a1..9eacccb 100644
--- a/hw/esp.c
+++ b/hw/esp.c
@@ -650,12 +650,14 @@
 {
     DeviceState *dev;
     SysBusDevice *s;
+    ESPState *esp;
 
     dev = qdev_create(NULL, "esp");
-    qdev_set_prop_ptr(dev, "dma_memory_read", dma_memory_read);
-    qdev_set_prop_ptr(dev, "dma_memory_write", dma_memory_write);
-    qdev_set_prop_ptr(dev, "dma_opaque", dma_opaque);
-    qdev_set_prop_int(dev, "it_shift", it_shift);
+    esp = DO_UPCAST(ESPState, busdev.qdev, dev);
+    esp->dma_memory_read = dma_memory_read;
+    esp->dma_memory_write = dma_memory_write;
+    esp->dma_opaque = dma_opaque;
+    esp->it_shift = it_shift;
     qdev_init(dev);
     s = sysbus_from_qdev(dev);
     sysbus_connect_irq(s, 0, irq);
@@ -668,11 +670,7 @@
     int esp_io_memory;
 
     sysbus_init_irq(dev, &s->irq);
-    s->it_shift = qdev_get_prop_int(&dev->qdev, "it_shift", -1);
     assert(s->it_shift != -1);
-    s->dma_memory_read = qdev_get_prop_ptr(&dev->qdev, "dma_memory_read");
-    s->dma_memory_write = qdev_get_prop_ptr(&dev->qdev, "dma_memory_write");
-    s->dma_opaque = qdev_get_prop_ptr(&dev->qdev, "dma_opaque");
 
     esp_io_memory = cpu_register_io_memory(esp_mem_read, esp_mem_write, s);
     sysbus_init_mmio(dev, ESP_REGS << s->it_shift, esp_io_memory);