patch 8.2.4050: Vim9: need to prefix every item in an autoload script

Problem:    Vim9: need to prefix every item in an autoload script.
Solution:   First step in supporting "vim9script autoload" and "import
            autoload".
diff --git a/src/userfunc.c b/src/userfunc.c
index b772913..ecd2e7c 100644
--- a/src/userfunc.c
+++ b/src/userfunc.c
@@ -1608,7 +1608,7 @@
 	    p = name + 2;
 	    len -= 2;
 	}
-	import = find_imported(p, len, NULL);
+	import = find_imported(p, len, FALSE, NULL);
 
 	// imported function from another script
 	if (import != NULL)
@@ -4079,6 +4079,9 @@
 	    else
 		eap->skip = TRUE;
 	}
+
+//	if (is_export)
+//	    name = may_prefix_autoload(name);
     }
 
     // An error in a function call during evaluation of an expression in magic
@@ -4363,7 +4366,7 @@
 	{
 	    char_u *uname = untrans_function_name(name);
 
-	    import = find_imported(uname == NULL ? name : uname, 0, NULL);
+	    import = find_imported(uname == NULL ? name : uname, 0, FALSE, NULL);
 	}
 
 	if (fp != NULL || import != NULL)