patch 8.2.0916: mapping with partly modifyOtherKeys code does not work

Problem:    Mapping with partly modifyOtherKeys code does not work.
Solution:   If there is no mapping with a separate modifier include the
            modifier in the key and then try mapping again. (closes #6200)
diff --git a/src/proto/term.pro b/src/proto/term.pro
index d84823c..88fdcb8 100644
--- a/src/proto/term.pro
+++ b/src/proto/term.pro
@@ -68,6 +68,7 @@
 void del_termcode(char_u *name);
 void set_mouse_topline(win_T *wp);
 int is_mouse_topline(win_T *wp);
+int put_string_in_typebuf(int offset, int slen, char_u *string, int new_slen, char_u *buf, int bufsize, int *buflen);
 int decode_modifiers(int n);
 int check_termcode(int max_offset, char_u *buf, int bufsize, int *buflen);
 void term_get_fg_color(char_u *r, char_u *g, char_u *b);