libobs: Remove unused obs_*_info module pointer

These were likely originally used for the obs_*_get_module functions,
but no longer are. Additionally, they weren't even implemented for
anything but obs_source_info. Let's remove this before it hits stable.

libobs/obs-encoder.h

@@ -344,9 +344,6 @@ struct obs_encoder_info {
 
 	bool (*encode_texture2)(void *data, struct encoder_texture *texture, int64_t pts, uint64_t lock_key,
 				uint64_t *next_key, struct encoder_packet *packet, bool *received_packet);
-
-	/** Pointer to module that generated this encoder **/
-	obs_module_t *module;
 };
 
 EXPORT void obs_register_encoder_s(const struct obs_encoder_info *info, size_t size);