qdev: add qdev_prop_exists()

Function test whenever a driver has a specific property.
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

hw/qdev-properties.c

@@ -480,6 +480,11 @@ static Property *qdev_prop_find(DeviceState *dev, const char *name)
     return NULL;
 }
 
+int qdev_prop_exists(DeviceState *dev, const char *name)
+{
+    return qdev_prop_find(dev, name) ? true : false;
+}
+
 int qdev_prop_parse(DeviceState *dev, const char *name, const char *value)
 {
     Property *prop;

hw/qdev.h

@@ -249,6 +249,7 @@ extern PropertyInfo qdev_prop_pci_devfn;
 
 /* Set properties between creation and init.  */
 void *qdev_get_prop_ptr(DeviceState *dev, Property *prop);
+int qdev_prop_exists(DeviceState *dev, const char *name);
 int qdev_prop_parse(DeviceState *dev, const char *name, const char *value);
 void qdev_prop_set(DeviceState *dev, const char *name, void *src, enum PropertyType type);
 void qdev_prop_set_uint8(DeviceState *dev, const char *name, uint8_t value);