rustdoc: Fix a copy&paste bug in attr_parser tests

Author: brson

src/rustdoc/attr_parser.rs

@@ -320,15 +320,15 @@ fn parse_const_long_doc(
 fn should_parse_const_short_doc() {
     let source = "#[doc = \"description\"]";
     let attrs = test::parse_attributes(source);
-    let attrs = parse_fn(attrs);
+    let attrs = parse_const(attrs);
     assert attrs.desc == some("description");
 }
 
 #[test]
 fn should_parse_const_long_doc() {
     let source = "#[doc(brief = \"a\", desc = \"b\")]";
     let attrs = test::parse_attributes(source);
-    let attrs = parse_fn(attrs);
+    let attrs = parse_const(attrs);
     assert attrs.brief == some("a");
     assert attrs.desc == some("b");
 }