patch 8.2.0201: cannot assign to an imported variable

Problem:    Cannot assign to an imported variable.
Solution:   Make it work.
diff --git a/src/proto/vim9compile.pro b/src/proto/vim9compile.pro
index 4f06e9d..73cf13f 100644
--- a/src/proto/vim9compile.pro
+++ b/src/proto/vim9compile.pro
@@ -4,7 +4,7 @@
 char *vartype_name(vartype_T type);
 char *type_name(type_T *type, char **tofree);
 int get_script_item_idx(int sid, char_u *name, int check_writable);
-imported_T *find_imported(char_u *name, cctx_T *cctx);
+imported_T *find_imported(char_u *name, size_t len, cctx_T *cctx);
 char_u *to_name_end(char_u *arg);
 char_u *to_name_const_end(char_u *arg);
 int assignment_len(char_u *p, int *heredoc);