Define basic internal API for access control

This patch introduces the virAccessManagerPtr class as the
interface between virtualization drivers and the access
control drivers. The viraccessperm.h file defines the
various permissions that will be used for each type of object
libvirt manages

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>

include/libvirt/virterror.h

@@ -118,6 +118,8 @@ typedef enum {
     VIR_FROM_IDENTITY = 53,     /* Error from identity code */
     VIR_FROM_CGROUP = 54,       /* Error from cgroups */
 
+    VIR_FROM_ACCESS = 55,       /* Error from access control manager */
+
 # ifdef VIR_ENUM_SENTINELS
     VIR_ERR_DOMAIN_LAST
 # endif
@@ -290,6 +292,8 @@ typedef enum {
     VIR_ERR_AGENT_UNRESPONSIVE = 86,    /* guest agent is unresponsive,
                                            not running or not usable */
     VIR_ERR_RESOURCE_BUSY = 87,         /* resource is already in use */
+    VIR_ERR_ACCESS_DENIED = 88,         /* operation on the object/resource
+                                           was denied */
 } virErrorNumber;
 
 /**