patch 8.1.1124: insert completion flags are mixed up

Problem:    Insert completion flags are mixed up.
Solution:   Clean up flags use of ins_compl_add() and cp_flags.
diff --git a/src/proto/insexpand.pro b/src/proto/insexpand.pro
index 0281245..3d6da20 100644
--- a/src/proto/insexpand.pro
+++ b/src/proto/insexpand.pro
@@ -20,7 +20,7 @@
 int has_compl_option(int dict_opt);
 int vim_is_ctrl_x_key(int c);
 int ins_compl_accept_char(int c);
-int ins_compl_add_infercase(char_u *str, int len, int icase, char_u *fname, int dir, int flags);
+int ins_compl_add_infercase(char_u *str_arg, int len, int icase, char_u *fname, int dir, int cont_s_ipos);
 int ins_compl_has_shown_match(void);
 int ins_compl_long_shown_match(void);
 void completeopt_was_set(void);