Missing `vulkan_video_codecs_common` requirement for video headers

The video headers, e.g.:

```
#include "vk_video/vulkan_video_codec_h264std.h"
#include "vk_video/vulkan_video_codec_h264std_decode.h"
```

include a file `vk_video/vulkan_video_codecs_common.h`, but this is file is missing as a type and not marked as a requirement of the include types.

I think such dependencies should be correctly modeled in `vk.xml` for external generators, this currently breaks glad: https://github.com/Dav1dde/glad/issues/434

Start in vk.xml by locating the video header include types and checking how their dependencies are represented. Model vk_video/vulkan_video_codecs_common.h as a type and as a requirement of the affected includes, then verify that the generated dependency information covers the headers described in the issue.

Written by the indexing model from the issue text.