528575 avoid libvirtd crash on LCX domain autostart

https://bugzilla.redhat.com/show_bug.cgi?id=528575
virsh -c lxc:/// autostart vm1
was crashing the daemon

* src/lxc/lxc_conf.h src/lxc/lxc_conf.c: initialize the driver
  autostartDir to avoid a NULL reference and implement autostart for LXC

src/lxc/lxc_conf.c

@@ -102,6 +102,9 @@ int lxcLoadDriverConfig(lxc_driver_t *driver)
         goto no_memory;
     if ((driver->logDir = strdup(LXC_LOG_DIR)) == NULL)
         goto no_memory;
+    if ((driver->autostartDir = strdup(LXC_AUTOSTART_DIR)) == NULL)
+        goto no_memory;
+
 
     if ((filename = strdup(SYSCONF_DIR "/libvirt/lxc.conf")) == NULL)
         goto no_memory;

src/lxc/lxc_conf.h

@@ -36,6 +36,7 @@
 #define LXC_CONFIG_DIR SYSCONF_DIR "/libvirt/lxc"
 #define LXC_STATE_DIR LOCAL_STATE_DIR "/run/libvirt/lxc"
 #define LXC_LOG_DIR LOCAL_STATE_DIR "/log/libvirt/lxc"
+#define LXC_AUTOSTART_DIR LXC_CONFIG_DIR "/autostart"
 
 typedef struct __lxc_driver lxc_driver_t;
 struct __lxc_driver {