[MTL-006] DP: fix DP thread priority

After enabling deadline calculation DP threads began to lose priority
in relation to logger thread which currently is set to the same priority
but has zeroed deadline.
Since processing should be not disturbed by logging operations, the
ZEPHYR_DP_THREAD_PRIORITY must be set to lower value than logger.

Signed-off-by: Jaroslaw Stelter <Jaroslaw.Stelter@intel.com>

src/audio/pipeline/pipeline-schedule.c

@@ -48,7 +48,7 @@ DECLARE_SOF_UUID("dp-task", dp_task_uuid, 0xee755917, 0x96b9, 0x4130,
 /**
  * \brief a priority of the DP threads in the system.
  */
-#define ZEPHYR_DP_THREAD_PRIORITY (CONFIG_NUM_PREEMPT_PRIORITIES - 1)
+#define ZEPHYR_DP_THREAD_PRIORITY (CONFIG_NUM_PREEMPT_PRIORITIES - 2)
 
 #endif /* CONFIG_ZEPHYR_DP_SCHEDULER */