patch 8.2.3735: cannot use a lambda for 'imactivatefunc'

Problem:    Cannot use a lambda for 'imactivatefunc'.
Solution:   Add lambda support for 'imactivatefunc' and 'imstatusfunc'.
            (Yegappan Lakshmanan, closes #9275)
diff --git a/src/alloc.c b/src/alloc.c
index 42caa41..38b452c 100644
--- a/src/alloc.c
+++ b/src/alloc.c
@@ -440,6 +440,7 @@
     free_prev_shellcmd();
     free_regexp_stuff();
     free_tag_stuff();
+    free_xim_stuff();
     free_cd_dir();
 # ifdef FEAT_SIGNS
     free_signs();