qcacmn: Add support to enable tx hw latency stats at run time

This feature can be enabled runtime using sysfs interface.
Support is added to dump and clear the histogram stats.

The lower delay regions has to be more granular to indicate any
medium related issues for time sensitive XR applications.

Change-Id: I0a44a54d12d92ce016de349810cb2bedebaf9a58
CRs-Fixed: 2981006

dp/wifi3.0/be/dp_be_tx.c

@@ -272,7 +272,8 @@ void dp_tx_process_htt_completion_be(struct dp_soc *soc,
 
 		tid_stats = &pdev->stats.tid_stats.tid_tx_stats[ring_id][tid];
 
-		if (qdf_unlikely(pdev->delay_stats_flag))
+		if (qdf_unlikely(pdev->delay_stats_flag) ||
+		    qdf_unlikely(dp_is_vdev_tx_delay_stats_enabled(vdev)))
 			dp_tx_compute_delay(vdev, tx_desc, tid, ring_id);
 		if (tx_status < CDP_MAX_TX_HTT_STATUS)
 			tid_stats->htt_status_cnt[tx_status]++;
@@ -616,13 +617,7 @@ dp_tx_hw_enqueue_be(struct dp_soc *soc, struct dp_vdev *vdev,
 
 	dp_tx_set_min_rates_for_critical_frames(soc, hal_tx_desc_cached,
 						tx_desc->nbuf);
-
-	if (qdf_unlikely(vdev->pdev->delay_stats_flag) ||
-	    qdf_unlikely(wlan_cfg_is_peer_ext_stats_enabled(soc->wlan_cfg_ctx)) ||
-	    qdf_unlikely(soc->rdkstats_enabled) ||
-	    dp_tx_pkt_tracepoints_enabled())
-		tx_desc->timestamp = qdf_ktime_to_ms(qdf_ktime_real_get());
-
+	dp_tx_desc_set_ktimestamp(vdev, tx_desc);
 	dp_verbose_debug("length:%d , type = %d, dma_addr %llx, offset %d desc id %u",
 			 tx_desc->length,
 			 (tx_desc->flags & DP_TX_DESC_FLAG_FRAG),