nv-filters: Reallocate state when resetting AIGS filters

This properly allocates the temporal state variable used in AI
greenscreen effect, when the latter is reset.

Signed-off-by: pkv <pkv@obsproject.com>
This commit is contained in:
Internal Server Error - Gitea: Git with a cup of tea
500 Internal Server Error

Gitea Version: 1.28.0+dev-477-g8b6ad49a5f