qcacmn: Add support for asynchronous Host to Target connection

Add support for asynchronous Host to Target connection connection in
whcih packets can be queued in both interrrupt and process context.

Change-Id: I52f0f972b938a558e4ef3c13cf4d76aa3a63d58f
CRs-Fixed: 1092518

htc/htc_internal.h

@@ -135,6 +135,7 @@ typedef struct _HTC_ENDPOINT {
 	HTC_ENDPOINT_STATS endpoint_stats;     /* endpoint statistics */
 #endif
 	bool TxCreditFlowEnabled;
+	bool async_update;  /* packets can be queued asynchronously */
 } HTC_ENDPOINT;
 
 #ifdef HTC_EP_STAT_PROFILING