patch 8.1.0445: setting 'term' does not store location for termcap options

Problem:    Setting 'term' does not store location for termcap options.
Solution:   Set the script context for termcap options that are changed when
            'term' is set.
diff --git a/src/proto/option.pro b/src/proto/option.pro
index b65cb45..2280365 100644
--- a/src/proto/option.pro
+++ b/src/proto/option.pro
@@ -17,11 +17,13 @@
 void check_buf_options(buf_T *buf);
 void free_string_option(char_u *p);
 void clear_string_option(char_u **pp);
-void set_term_option_alloced(char_u **p);
+int get_term_opt_idx(char_u **p);
+int set_term_option_alloced(char_u **p);
 int was_set_insecurely(char_u *opt, int opt_flags);
 void set_string_option_direct(char_u *name, int opt_idx, char_u *val, int opt_flags, int set_sid);
 char_u *check_colorcolumn(win_T *wp);
 char_u *check_stl_option(char_u *s);
+void set_term_option_sctx_idx(char *name, int opt_idx);
 int get_option_value(char_u *name, long *numval, char_u **stringval, int opt_flags);
 int get_option_value_strict(char_u *name, long *numval, char_u **stringval, int opt_type, void *from);
 char_u *option_iter_next(void **option, int opt_type);