qcacld-3.0: Add handler for WMI_VDEV_BCN_LATENCY_EVENTID

WMI_VDEV_BCN_LATENCY_EVENTID is sent by firmware when it receives
the latency IE from connected AP in beacon.

Add handler for this event and when latency_level received is ultra
low in latency IE, update request pm qos type PM_QOS_CPU_DMA_LATENCY
to level DISABLE_KRAIT_IDLE_PS_VAL to speed up CPU efficiency and
irq response. This is needed for Voice and Music products where extreme
low latency is needed while playing music and high power consumption is
accepted.

Change-Id: I3c63ef247f4f4a1add68111ef1bcee6daafd148a
CRs-Fixed: 2723205

core/hdd/inc/wlan_hdd_main.h

@@ -4484,4 +4484,18 @@ int hdd_update_phymode(struct hdd_adapter *adapter, eCsrPhyMode phymode,
  */
 bool hdd_max_sta_vdev_count_reached(struct hdd_context *hdd_ctx);
 
+#if defined(CLD_PM_QOS) && defined(WLAN_FEATURE_LL_MODE)
+/**
+ * hdd_beacon_latency_event_cb() - Callback function to get latency level
+ * @latency_level: latency level received from firmware
+ *
+ * Return: None
+ */
+void hdd_beacon_latency_event_cb(uint32_t latency_level);
+#else
+static inline void hdd_beacon_latency_event_cb(uint32_t latency_level)
+{
+}
+#endif
+
 #endif /* end #if !defined(WLAN_HDD_MAIN_H) */