qcacld-3.0: do fisa flush per vdev only if fisa enabled in INI

If FISA related macro WLAN_SUPPORT_RX_FISA is configured but INI
dp_rx_fisa_enable is not set, fisa related context is not initialed
in dp_soc structure. if do fisa flush when vdev detach, invalid
access to fisa context will happen.

Do fisa flush per vdev only if fisa is enabled in INI.

Change-Id: Id3cecfa24f8ce26465a7809d4d9b2e92ae199c7d
CRs-Fixed: 2687949

core/hdd/src/wlan_hdd_tx_rx.c

@@ -2063,7 +2063,8 @@ QDF_STATUS hdd_rx_flush_packet_cbk(void *adapter_context, uint8_t vdev_id)
 	}
 
 	/* do fisa flush for this vdev */
-	hdd_rx_fisa_flush_by_vdev_id(soc, vdev_id);
+	if (hdd_ctx->config->fisa_enable)
+		hdd_rx_fisa_flush_by_vdev_id(soc, vdev_id);
 
 	if (hdd_ctx->enable_dp_rx_threads)
 		dp_txrx_flush_pkts_by_vdev_id(soc, vdev_id);