To support the SiWx917 SNTP Network Stack Application protocol

offloading, we need to add the Silicon Labs APIs,
so adding the corresponding source files and include files

Required Zlib licensing to push to upstream
Co-authored-by: Swami Das Nampalli <swami.das@silabs.com>
Signed-off-by: Swami Das Nampalli <swami.das@silabs.com>
Signed-off-by: Rahul Gurram <rahul.gurram@silabs.com>

Author: ragurram26

wiseconnect/components/device/silabs/si91x/wireless/inc/sntp/si91x_sntp_client_callback_framework.h

@@ -0,0 +1,21 @@
+/*******************************************************************************
+* @file  si91x_sntp_client_callback_framework.h
+* @brief 
+*******************************************************************************
+* # License
+* <b>Copyright 2023 Silicon Laboratories Inc. www.silabs.com</b>
+*******************************************************************************
+*
+* The licensor of this software is Silicon Laboratories Inc. Your use of this
+* software is governed by the terms of Silicon Labs Master Software License
+* Agreement (MSLA) available at
+* www.silabs.com/about-us/legal/master-software-license-agreement. This
+* software is distributed to you in Source Code format and is governed by the
+* sections of the MSLA applicable to Source Code.
+*
+******************************************************************************/
+#pragma once
+
+#include "sl_si91x_types.h"
+
+sl_status_t sli_si91x_sntp_event_handler(sli_si91x_queue_packet_t *data);

wiseconnect/components/device/silabs/si91x/wireless/inc/sntp/si91x_sntp_client_types.h

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+/*******************************************************************************
+* @file  si91x_sntp_client_types.h
+* @brief 
+*******************************************************************************
+* # License
+* <b>Copyright 2023 Silicon Laboratories Inc. www.silabs.com</b>
+*******************************************************************************
+*
+* The licensor of this software is Silicon Laboratories Inc. Your use of this
+* software is governed by the terms of Silicon Labs Master Software License
+* Agreement (MSLA) available at
+* www.silabs.com/about-us/legal/master-software-license-agreement. This
+* software is distributed to you in Source Code format and is governed by the
+* sections of the MSLA applicable to Source Code.
+*
+******************************************************************************/
+#pragma once
+#include "stdint.h"
+/******************************************************
+ * *                      Macros
+ * ******************************************************/
+//SNTP client feature
+#define SI91X_SNTP_CLIENT_CREATE            1
+#define SI91X_SNTP_CLIENT_GETTIME           2
+#define SI91X_SNTP_CLIENT_GETTIME_DATE      3
+#define SI91X_SNTP_CLIENT_GETSERVER_ADDRESS 4
+#define SI91X_SNTP_CLIENT_DELETE            5
+#define SI91X_SNTP_CLIENT_GET_SERVER_INFO   6
+#define SI91X_SNTP_CLIENT_SERVER_ASYNC_RSP  7
+
+/******************************************************
+ * *                 Type Definitions
+ * ******************************************************/
+
+// Define for SNTP client initialization
+typedef struct {
+  uint8_t command_type;
+  uint8_t ip_version;
+  union {
+    uint8_t ipv4_address[4];
+    uint8_t ipv6_address[16];
+  } server_ip_address;
+  uint8_t sntp_method;
+  uint8_t sntp_timeout[2];
+} si91x_sntp_client_t;
+
+typedef struct {
+  uint8_t command_type;
+  uint8_t ip_version;
+  union {
+    uint8_t ipv4_address[4];
+    uint8_t ipv6_address[16];
+  } server_ip_address;
+  uint8_t sntp_method;
+} si91x_sntp_server_info_rsp_t;
+
+typedef struct {
+  uint8_t ip_version;
+  union {
+    uint8_t ipv4_address[4];
+    uint8_t ipv6_address[16];
+  } server_ip_address;
+  uint8_t sntp_method;
+} si91x_sntp_server_rsp_t;