bus: fsl-mc: add fsl_mc_allocator cleanup function

The userspace support for fsl-mc requires a fsl_mc_allocator
cleanup function. Add the needed function.

Signed-off-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/bus/fsl-mc/fsl-mc-allocator.c b/drivers/bus/fsl-mc/fsl-mc-allocator.c
index 452c5d7..fb1442b 100644
--- a/drivers/bus/fsl-mc/fsl-mc-allocator.c
+++ b/drivers/bus/fsl-mc/fsl-mc-allocator.c
@@ -646,3 +646,8 @@ int __init fsl_mc_allocator_driver_init(void)
 {
 	return fsl_mc_driver_register(&fsl_mc_allocator_driver);
 }
+
+void fsl_mc_allocator_driver_exit(void)
+{
+	fsl_mc_driver_unregister(&fsl_mc_allocator_driver);
+}