(API Change) libobs: Add _FLAG to source flags

Changes OBS_SOURCE_UNBUFFERED to OBS_SOURCE_FLAG_UNBUFFERED to make
naming a bit better for source flags.

libobs/obs-source.c

@@ -1553,7 +1553,7 @@ static bool ready_async_frame(obs_source_t *source, uint64_t sys_time)
 	uint64_t frame_time = next_frame->timestamp;
 	uint64_t frame_offset = 0;
 
-	if ((source->flags & OBS_SOURCE_UNBUFFERED) != 0) {
+	if ((source->flags & OBS_SOURCE_FLAG_UNBUFFERED) != 0) {
 		while (source->video_frames.num > 1) {
 			da_erase(source->video_frames, 0);
 			obs_source_frame_destroy(next_frame);

libobs/obs.h

@@ -752,7 +752,7 @@ EXPORT void obs_source_save(obs_source_t *source);
 EXPORT void obs_source_load(obs_source_t *source);
 
 /** Specifies that async video frames should be played as soon as possible */
-#define OBS_SOURCE_UNBUFFERED (1<<0)
+#define OBS_SOURCE_FLAG_UNBUFFERED             (1<<0)
 
 /** Sets source flags.  Note that these are different from the main output
  * flags. */