patch 8.2.3619: cannot use a lambda for 'operatorfunc'

Problem:    Cannot use a lambda for 'operatorfunc'.
Solution:   Support using a lambda or partial. (Yegappan Lakshmanan,
            closes #8775)
diff --git a/src/proto/ops.pro b/src/proto/ops.pro
index cbe49cc..c46af05 100644
--- a/src/proto/ops.pro
+++ b/src/proto/ops.pro
@@ -17,5 +17,7 @@
 void op_addsub(oparg_T *oap, linenr_T Prenum1, int g_cmd);
 void clear_oparg(oparg_T *oap);
 void cursor_pos_info(dict_T *dict);
+int set_operatorfunc_option(void);
+void free_operatorfunc_option(void);
 void do_pending_operator(cmdarg_T *cap, int old_col, int gui_yank);
 /* vim: set ft=c : */