libxl: Move driver lock/unlock to libxl_conf

Move the libxl driver lock/unlock functions from libxl_driver.c
to libxl_conf.h so they can be used by other source files.

src/libxl/libxl_conf.h

@@ -150,4 +150,16 @@ int
 libxlBuildDomainConfig(libxlDriverPrivatePtr driver,
                        virDomainObjPtr vm, libxl_domain_config *d_config);
 
+static inline void
+libxlDriverLock(libxlDriverPrivatePtr driver)
+{
+    virMutexLock(&driver->lock);
+}
+
+static inline void
+libxlDriverUnlock(libxlDriverPrivatePtr driver)
+{
+    virMutexUnlock(&driver->lock);
+}
+
 #endif /* LIBXL_CONF_H */

src/libxl/libxl_driver.c

@@ -77,18 +77,6 @@ static int
 libxlVmStart(libxlDriverPrivatePtr driver, virDomainObjPtr vm,
              bool start_paused, int restore_fd);
 
-static void
-libxlDriverLock(libxlDriverPrivatePtr driver)
-{
-    virMutexLock(&driver->lock);
-}
-
-static void
-libxlDriverUnlock(libxlDriverPrivatePtr driver)
-{
-    virMutexUnlock(&driver->lock);
-}
-
 /* driver must be locked before calling */
 static void
 libxlDomainEventQueue(libxlDriverPrivatePtr driver, virDomainEventPtr event)