[runtime/tools] Fix clang-tidy invocation
[runtime/tools] Fix clang-tidy invocation

c++17 should be passed to -std=... and not to -x option.

Change-Id: I13e21d0ec98bcebe2ca537903e1bd399e287852a
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/198401
Reviewed-by: Clement Skau <495593248b6158163719b90dde8357b589c8e5d0@google.com>
Commit-Queue: Vyacheslav Egorov <72c81f38df725d8f1832acb9b5bb99563fc2f1b9@google.com>

dart-lang/sdk,dart-lang/sdk,dart-lang/sdk,dart-lang/sdk,dart-lang/sdk,dart-lang/sdk,dart-lang/sdk,dart-lang/sdk