Fix tests after two-phase borrow rewrite

src/test/compile-fail/nll/region-ends-after-if-condition.rs

@@ -12,7 +12,7 @@
 // in the type of `p` includes the points after `&v[0]` up to (but not
 // including) the call to `use_x`. The `else` branch is not included.
 
-// compile-flags:-Zborrowck=compare -Znll
+// compile-flags:-Zborrowck=compare -Znll -Ztwo-phase-borrows
 
 #![allow(warnings)]
 #![feature(rustc_attrs)]

src/test/ui/issue-45157.rs

@@ -37,7 +37,6 @@ fn main() {
         let nref = &u.z.c;
         //~^ ERROR cannot borrow `u.z.c` as immutable because it is also borrowed as mutable [E0502]
         println!("{} {}", mref, nref)
-        //~^ ERROR cannot borrow `u.s.a` as mutable because it is also borrowed as immutable [E0502]
     }
 }
 

src/test/ui/issue-45157.stderr

@@ -10,17 +10,6 @@ LL |         //~^ ERROR cannot borrow `u.z.c` as immutable because it is also bo
 LL |         println!("{} {}", mref, nref)
    |                           ---- borrow later used here
 
-error[E0502]: cannot borrow `u.s.a` as mutable because it is also borrowed as immutable
-  --> $DIR/issue-45157.rs:39:27
-   |
-LL |         let nref = &u.z.c;
-   |                    ------ immutable borrow occurs here
-LL |         //~^ ERROR cannot borrow `u.z.c` as immutable because it is also borrowed as mutable [E0502]
-LL |         println!("{} {}", mref, nref)
-   |                           ^^^^  ---- borrow later used here
-   |                           |
-   |                           mutable borrow occurs here
-
-error: aborting due to 2 previous errors
+error: aborting due to previous error
 
 If you want more information on this error, try using "rustc --explain E0502"