patch 8.1.0475: memory not freed on exit when quit in autocmd

Problem:    Memory not freed on exit when quit in autocmd.
Solution:   Remember funccal stack when executing autocmd.
diff --git a/src/version.c b/src/version.c
index 5190030..4523c71 100644
--- a/src/version.c
+++ b/src/version.c
@@ -793,6 +793,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    475,
+/**/
     474,
 /**/
     473,