Fix license header in several code files

***NO_CI***

Author: josesimoes

src/CLR/CorLib/corlib_native_System_Threading_Interlocked.cpp

@@ -3,6 +3,7 @@
 // Portions Copyright (c) Microsoft Corporation.  All rights reserved.
 // See LICENSE file in the project root for full license information.
 //
+
 #include "CorLib.h"
 
 HRESULT Library_corlib_native_System_Threading_Interlocked::Increment___STATIC__I4__BYREF_I4(CLR_RT_StackFrame &stack)

src/CLR/CorLib/corlib_native_System_Threading_SpinWait.cpp

@@ -1,14 +1,8 @@
-//-----------------------------------------------------------------------------
 //
-//                   ** WARNING! **
-//    This file was generated automatically by a tool.
-//    Re-running the tool will overwrite this file.
-//    You should copy this file to a custom location
-//    before adding any customization in the copy to
-//    prevent loss of your changes when the tool is
-//    re-run.
+// Copyright (c) .NET Foundation and Contributors
+// Portions Copyright (c) Microsoft Corporation.  All rights reserved.
+// See LICENSE file in the project root for full license information.
 //
-//-----------------------------------------------------------------------------
 
 #include "corlib_native.h"
 

src/DeviceInterfaces/Networking.Sntp/nf_networking_sntp_nanoFramework_Networking_Sntp_stubs.cpp

@@ -1,14 +1,8 @@
-//-----------------------------------------------------------------------------
 //
-//                   ** WARNING! **
-//    This file was generated automatically by a tool.
-//    Re-running the tool will overwrite this file.
-//    You should copy this file to a custom location
-//    before adding any customization in the copy to
-//    prevent loss of your changes when the tool is
-//    re-run.
+// Copyright (c) .NET Foundation and Contributors
+// Portions Copyright (c) Microsoft Corporation.  All rights reserved.
+// See LICENSE file in the project root for full license information.
 //
-//-----------------------------------------------------------------------------
 
 #include "nf_networking_sntp.h"
 

src/System.Device.Adc/sys_dev_adc_native_System_Device_Adc_AdcChannel_stubs.cpp

@@ -1,14 +1,8 @@
-//-----------------------------------------------------------------------------
 //
-//                   ** WARNING! **
-//    This file was generated automatically by a tool.
-//    Re-running the tool will overwrite this file.
-//    You should copy this file to a custom location
-//    before adding any customization in the copy to
-//    prevent loss of your changes when the tool is
-//    re-run.
+// Copyright (c) .NET Foundation and Contributors
+// Portions Copyright (c) Microsoft Corporation.  All rights reserved.
+// See LICENSE file in the project root for full license information.
 //
-//-----------------------------------------------------------------------------
 
 #include "sys_dev_adc_native.h"
 

src/System.Device.Adc/sys_dev_adc_native_System_Device_Adc_AdcController_stubs.cpp

@@ -1,14 +1,8 @@
-//-----------------------------------------------------------------------------
 //
-//                   ** WARNING! **
-//    This file was generated automatically by a tool.
-//    Re-running the tool will overwrite this file.
-//    You should copy this file to a custom location
-//    before adding any customization in the copy to
-//    prevent loss of your changes when the tool is
-//    re-run.
+// Copyright (c) .NET Foundation and Contributors
+// Portions Copyright (c) Microsoft Corporation.  All rights reserved.
+// See LICENSE file in the project root for full license information.
 //
-//-----------------------------------------------------------------------------
 
 #include "sys_dev_adc_native.h"