Fix accidental assignment inside test asserts

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@314947 91177308-0d34-0410-b5e6-96231b3b80d8

test/std/utilities/utility/pairs/pairs.pair/const_pair_U_V.pass.cpp

@@ -71,7 +71,7 @@ int main()
         P1 p1(42, 101);
         P2 p2(p1);
         assert(p2.first == 42);
-        assert(p2.second = 101);
+        assert(p2.second == 101);
     }
     {
         test_pair_const<AllCtors, AllCtors>(); // copy construction

test/std/utilities/utility/pairs/pairs.pair/rv_pair_U_V.pass.cpp

@@ -81,7 +81,7 @@ int main()
         P1 p1(42, 101);
         P2 p2(std::move(p1));
         assert(p2.first == 42);
-        assert(p2.second = 101);
+        assert(p2.second == 101);
     }
     {
         test_pair_rv<AllCtors, AllCtors>();