fix memory leak in recv()

[schoeler]

fix memory leak in recv() due to early return causing sl_91x_host_free_buffer() to never be called found during port from wiseconnect SDK 2.0 to wiseconnect SDK 3.0 causing malloc() failure after running for several minutes

[schoeler]

It appears the VERIFY_STATUS_AND_RETURN() pattern is used throughout the SDK codebase and by design, this memory leak could also occur in

• close()
• select()
• sl_wifi_connect()
• sl_wifi_get_signal_strength()
• sl_wifi_get_mac_address()
• sl_wifi_get_channel()
• sl_wifi_start_ap()
• sl_wifi_get_pairwise_master_key()
• sl_wifi_get_ap_client_info()
• sl_wifi_get_firmware_version()
• sl_wifi_get_statistics()
• sl_wifi_generate_wps_pin()
• sl_dns_host_get_by_name()
• sl_wifi_wait_for_scan_results()
• sl_si91x_configure_ip_address()
• sl_si91x_ota_firmware_upgradation()
• sl_si91x_recvfrom()
• sl_si91x_select()
• etc

I would recommend either removing the *_RETURN() pattern, or using the VERIFY_STATUS_AND_GOTO() pattern as used in sl_sntp.c

Please advise how to proceed with this.