[libcxx] [test] D27023: Fix MSVC warning C4389 "signed/unsigned mismatch", part 10/12.

Add static_cast<int>. In these cases, the values are guaranteed to be small-ish,
and they're being compared to int elements.

test/std/containers/sequences/deque/deque.capacity/access.pass.cpp
Use int instead of unsigned to iterate from 0 to 10.

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@288747 91177308-0d34-0410-b5e6-96231b3b80d8

test/std/algorithms/alg.nonmodifying/alg.foreach/test.pass.cpp

@@ -35,5 +35,5 @@ int main()
                                     for_each_test(0));
     assert(f.count == s);
     for (unsigned i = 0; i < s; ++i)
-        assert(ia[i] == i+1);
+        assert(ia[i] == static_cast<int>(i+1));
 }