qcacmn: improve mboxping TX t-put for SDIO project

qcacld-2.0 to qcacmn propagation

Return HTC_SEND_FULL_KEEP directly in epping_tx_queue_full function
and give nodrop pkts higher priority over normal pkts

Change-Id: Ib36e1a9f34eb9054b12f0e8ba54a86ace7d6c8f8
CRs-Fixed: 990726

htc/htc_api.h

@@ -637,6 +637,19 @@ A_STATUS htc_add_receive_pkt_multiple(HTC_HANDLE HTCHandle,
 bool htc_is_endpoint_active(HTC_HANDLE HTCHandle,
 			      HTC_ENDPOINT_ID Endpoint);
 
+/*+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
+   @desc: Set up nodrop pkt flag for mboxping nodrop pkt
+   @function name: htc_set_nodrop_pkt
+   @input:  HTCHandle - HTC handle
+	isNodropPkt - indicates whether it is nodrop pkt
+   @output:
+   @return:
+   @notes:
+   @example:
+   @see also:
+ +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/
+void htc_set_nodrop_pkt(HTC_HANDLE HTCHandle, A_BOOL isNodropPkt);
+
 /*+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
    @desc: Get the number of recv buffers currently queued into an HTC endpoint
    @function name: htc_get_num_recv_buffers