patch 9.0.1041: cannot define a method in a class

Problem:    Cannot define a method in a class.
Solution:   Implement defining an object method.  Make calling an object
            method work.
diff --git a/src/eval.c b/src/eval.c
index 703e1ea..0a0a1e1 100644
--- a/src/eval.c
+++ b/src/eval.c
@@ -295,7 +295,7 @@
 
 	    // Shortcut to call a compiled function with minimal overhead.
 	    r = call_def_function(partial->pt_func, argc, argv,
-					  DEF_USE_PT_ARGV, partial, fc, rettv);
+				    DEF_USE_PT_ARGV, partial, NULL, fc, rettv);
 	    if (fc_arg == NULL)
 		remove_funccal();
 	    if (r == FAIL)