improve conflict error reporting

src/test/compile-fail/borrowck/borrowck-local-borrow-outlives-fn.rs

@@ -13,7 +13,7 @@
 
 fn cplusplus_mode(x: isize) -> &'static isize {
     &x //[ast]~ ERROR `x` does not live long enough
-       //[mir]~^ ERROR borrowed value does not live long enough
 }
+//[mir]~^ ERROR borrowed value does not live long enough
 
 fn main() {}

src/test/compile-fail/borrowck/borrowck-local-borrow-with-panic-outlives-fn.rs

@@ -14,9 +14,9 @@
 fn cplusplus_mode_exceptionally_unsafe(x: &mut Option<&'static mut isize>) {
     let mut z = (0, 0);
     *x = Some(&mut z.1); //[ast]~ ERROR [E0597]
-                         //[mir]~^ ERROR [E0597]
     panic!("catch me for a dangling pointer!")
 }
+//[mir]~^ ERROR [E0597]
 
 fn main() {
     cplusplus_mode_exceptionally_unsafe(&mut None);