[SMTChecker] Loops are unrolled once

test/libsolidity/smtCheckerTests/loops/while_loop_simple_1.sol

@@ -4,10 +4,10 @@ contract C {
     function f(uint x) public pure {
         x = 2;
         while (x > 1) {
-            x = 2;
+            x = 1;
         }
         assert(x == 2);
     }
 }
 // ----
-// Warning: (194-208): Assertion violation happens here\nNote that some information is erased after the execution of loops.\nYou can re-introduce information using require().
+// Warning: (194-208): Assertion violation happens here