sparc: fix spec, it's called dump_func not dump_node

ir/be/sparc/sparc_spec.pl

@@ -284,13 +284,13 @@ AddCC_t => {
 	ins       => [ "left", "right" ],
 	outs      => [ "res", "flags" ],
 	attr_type => "",
-	dump_node => "NULL",
+	dump_func => "NULL",
 },
 
 AddX_t => {
 	ins       => [ "left", "right", "flags_input" ],
 	attr_type => "",
-	dump_node => "NULL",
+	dump_func => "NULL",
 },
 
 Sub => {
@@ -318,13 +318,13 @@ SubCC_t => {
 	ins       => [ "left", "right" ],
 	outs      => [ "res", "flags" ],
 	attr_type => "",
-	dump_node => "NULL",
+	dump_func => "NULL",
 },
 
 SubX_t => {
 	ins       => [ "left", "right", "flags_input" ],
 	attr_type => "",
-	dump_node => "NULL",
+	dump_func => "NULL",
 },
 
 # Load / Store