d3d9/tests: Fix a typo in skip() message

[Henri Verbeet]

On 1 May 2016 at 10:53, Andrey Gusev <andrey.goosev at gmail.com> wrote:
> -        skip("Failed to create a vetex shader\n");
> +        skip("Failed to create a vertex shader\n");
The typo fix is fine of course, but if you're going to touch the line
please fix the punctuation as well.