Convert builtin lints to uppercase names for style consistency

Author: Keegan McAllister

src/librustc/driver/driver.rs

@@ -786,15 +786,15 @@ pub fn collect_crate_types(session: &Session,
                 }
                 Some(ref n) if n.equiv(&("bin")) => Some(config::CrateTypeExecutable),
                 Some(_) => {
-                    session.add_lint(lint::builtin::unknown_crate_type,
+                    session.add_lint(lint::builtin::UNKNOWN_CRATE_TYPE,
                                      ast::CRATE_NODE_ID,
                                      a.span,
                                      "invalid `crate_type` \
                                       value".to_string());
                     None
                 }
                 _ => {
-                    session.add_lint(lint::builtin::unknown_crate_type,
+                    session.add_lint(lint::builtin::UNKNOWN_CRATE_TYPE,
                                      ast::CRATE_NODE_ID,
                                      a.span,
                                      "`crate_type` requires a \

src/librustc/front/feature_gate.rs

@@ -409,7 +409,7 @@ pub fn check_crate(sess: &Session, krate: &ast::Crate) {
                                                      directive not necessary");
                         }
                         None => {
-                            sess.add_lint(lint::builtin::unknown_features,
+                            sess.add_lint(lint::builtin::UNKNOWN_FEATURES,
                                           ast::CRATE_NODE_ID,
                                           mi.span,
                                           "unknown feature".to_string());