linux-v4l2: Expand packed values to 4 bytes

These days you might capture card a 175Hz monitor with a framerate
defined as 10000000/57143 that doesnt fit in a short. And reporting a
negative FPS in that case isnt very helpful.
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Internal Server Error - Gitea: Git with a cup of tea
500 Internal Server Error

Gitea Version: 1.28.0+dev-477-g8b6ad49a5f