patch 9.0.1262: the did_set_string_option function is too long

Problem:    The did_set_string_option function is too long.
Solution:   Split off functionality to individual functions.  (Yegappan
            Lakshmanan, Lewis Russell, closes #11904)
diff --git a/src/proto/gui_xim.pro b/src/proto/gui_xim.pro
index 8c5c53a..2e944ae 100644
--- a/src/proto/gui_xim.pro
+++ b/src/proto/gui_xim.pro
@@ -1,6 +1,6 @@
 /* gui_xim.c */
-int set_imactivatefunc_option(void);
-int set_imstatusfunc_option(void);
+char *set_imactivatefunc_option(void);
+char *set_imstatusfunc_option(void);
 void free_xim_stuff(void);
 int set_ref_in_im_funcs(int copyID);
 void im_set_active(int active);