qcacld-3.0: Fix compile issue when WLAN_DEBUG is not enabled

For some branches, we disabled BUILD_DEBUG_VERSION, to avoid compile
issues, add macro for new function which only will be used at
QDF_TRACE().

Change-Id: Idd0bb3a98ef92b837e14bd4e8e3c374b1b6a7e58
CRs-Fixed: 2492501

core/sap/src/sap_module.c

@@ -1335,6 +1335,7 @@ static inline void sap_start_csa_restart(struct mac_context *mac,
  *
  * Return: string reason
  */
+#ifdef WLAN_DEBUG
 static char *sap_get_csa_reason_str(enum sap_csa_reason_code reason)
 {
 	switch (reason) {
@@ -1360,6 +1361,7 @@ static char *sap_get_csa_reason_str(enum sap_csa_reason_code reason)
 		return "UNKNOWN";
 	}
 }
+#endif
 
 /**
  * wlansap_set_channel_change_with_csa() - Set channel change with CSA