Add PlatformCapabilities and TargetCapabilities

- Following nanoframework/nf-debugger#202.

targets/FreeRTOS/GC5/common/targetHAL.c

@@ -7,6 +7,7 @@
 #include "stdbool.h"
 #include "cmsis_gcc.h"
 #include <nanoWeak.h>
+#include <platform_target_capabilities.h>
 
 void HAL_AssertEx()
 {
@@ -36,3 +37,16 @@ bool Target_HasNanoBooter()
 { 
     return true; 
 };
+
+// declarations of platform capabilities
+uint32_t GetPlatformCapabilities()
+{ 
+    return 0; 
+};
+
+// declarations of target capabilities
+// If a target has something to declare it has to provide a 'strong' implementation of this.
+__nfweak uint32_t GetTargetCapabilities()
+{ 
+    return TargetCapabilities_JtagUpdate; 
+};

targets/FreeRTOS/GC5/include/platform_target_capabilities.h

@@ -0,0 +1,25 @@
+//
+// Copyright (c) 2019 The nanoFramework project contributors
+// See LICENSE file in the project root for full license information.
+//
+
+#ifndef _PLATFORM_TARGET_CAPABILITIES_H_
+#define _PLATFORM_TARGET_CAPABILITIES_H_ 1
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////
+// !!! KEEP IN SYNC WITH nanoFramework.Tools.Debugger.Esp32.TargetCapabilities (in managed code) !!! //
+///////////////////////////////////////////////////////////////////////////////////////////////////////
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+// this platform doesn't have any declared capabilities
+
+// the targets of this platform don't have any declared capabilities
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif //_PLATFORM_TARGET_CAPABILITIES_H_