audio: move cir_buf_ptr to common header

This moves struct cir_buf_ptr from mixin_mixout to a common header so it
can be reused by other modules.

Signed-off-by: Serhiy Katsyuba <serhiy.katsyuba@intel.com>

Author: serhiy-katsyuba-intel

src/audio/mixin_mixout/mixin_mixout.h

@@ -99,13 +99,6 @@ struct ipc4_mixer_mode_config {
 	struct ipc4_mixer_mode_sink_config mixer_mode_sink_configs[1];
 } __packed __aligned(4);
 
-/* Pointer to data in circular buffer together with buffer boundaries */
-struct cir_buf_ptr {
-	void *buf_start;
-	void *buf_end;
-	void *ptr;
-};
-
 /**
  * \brief mixin processing function interface
  */

src/include/sof/audio/audio_stream.h

@@ -66,6 +66,15 @@ struct audio_stream {
 	struct sof_audio_stream_params runtime_stream_params;
 };
 
+/* A pointer to data in a ring buffer. Just for convenience to reduce the number of typical
+ * processing function parameters: e.g., just 3 parameters (in, out ptr, and size) instead of 7.
+ */
+struct cir_buf_ptr {
+	void *buf_start;
+	void *buf_end;
+	void *ptr;
+};
+
 void audio_stream_recalc_align(struct audio_stream *stream);
 
 static inline void *audio_stream_get_rptr(const struct audio_stream *buf)