qcacmn: Fix -Wmissing-prototypes in Host Transport layer

We want to enable the compiler's -Wmissing-prototypes switch, but
there is existing code that is generating warnings. Fix all warnings
in the Host Transport layer.

Change-Id: Ic9c7f920883f41176d89419de25b7e02df0b895e
CRs-Fixed: 1093231

htc/htc.c

@@ -342,7 +342,7 @@ void *htc_get_hif_device(HTC_HANDLE HTCHandle)
 	return target->hif_dev;
 }
 
-void htc_control_tx_complete(void *Context, HTC_PACKET *pPacket)
+static void htc_control_tx_complete(void *Context, HTC_PACKET *pPacket)
 {
 	HTC_TARGET *target = (HTC_TARGET *) Context;
 	AR_DEBUG_PRINTF(ATH_DEBUG_TRC,
@@ -394,6 +394,7 @@ htc_setup_epping_credit_allocation(struct hif_opaque_softc *scn,
  *
  * Return: A_STATUS
  */
+static
 A_STATUS htc_setup_target_buffer_assignments(HTC_TARGET *target)
 {
 	HTC_SERVICE_TX_CREDIT_ALLOCATION *pEntry;

htc/htc_send.c

@@ -751,9 +751,9 @@ static void queue_htc_pm_packets(HTC_ENDPOINT *endpoint,
  *
  * Return: None
  */
-void get_htc_send_packets_credit_based(HTC_TARGET *target,
-				       HTC_ENDPOINT *pEndpoint,
-				       HTC_PACKET_QUEUE *pQueue)
+static void get_htc_send_packets_credit_based(HTC_TARGET *target,
+					      HTC_ENDPOINT *pEndpoint,
+					      HTC_PACKET_QUEUE *pQueue)
 {
 	int creditsRequired;
 	int remainder;
@@ -888,9 +888,9 @@ void get_htc_send_packets_credit_based(HTC_TARGET *target,
 
 }
 
-void get_htc_send_packets(HTC_TARGET *target,
-			  HTC_ENDPOINT *pEndpoint,
-			  HTC_PACKET_QUEUE *pQueue, int Resources)
+static void get_htc_send_packets(HTC_TARGET *target,
+				 HTC_ENDPOINT *pEndpoint,
+				 HTC_PACKET_QUEUE *pQueue, int Resources)
 {
 
 	HTC_PACKET *pPacket;