thinkpad_acpi: fix rfkill memory leak on unload

rfkill_unregister() should always be followed by rfkill_destroy()

Signed-off-by: Corentin Chary <corentincj@iksaif.net>
Acked-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/drivers/platform/x86/thinkpad_acpi.c b/drivers/platform/x86/thinkpad_acpi.c
index 955adf6..f78d275 100644
--- a/drivers/platform/x86/thinkpad_acpi.c
+++ b/drivers/platform/x86/thinkpad_acpi.c
@@ -1278,6 +1278,7 @@
 	tp_rfk = tpacpi_rfkill_switches[id];
 	if (tp_rfk) {
 		rfkill_unregister(tp_rfk->rfkill);
+		rfkill_destroy(tp_rfk->rfkill);
 		tpacpi_rfkill_switches[id] = NULL;
 		kfree(tp_rfk);
 	}