runtime: sprinkle some linker pragmas to autolink

This prepares the runtime to be closed with its dependencies when
performing static linking. The pragma ensures that the linker will
automatically pick up the dependent libraries avoiding the need to
explicitly add the dependencies.

stdlib/public/runtime/Errors.cpp

@@ -19,6 +19,8 @@
 #define NOMINMAX
 #include <windows.h>
 
+#pragma comment(lib, "User32.Lib")
+
 #include <mutex>
 #endif
 

stdlib/public/runtime/ImageInspectionCOFF.cpp

@@ -21,6 +21,8 @@
 #define NOMINMAX
 #include <Windows.h>
 #include <DbgHelp.h>
+
+#pragma comment(lib, "DbgHelp.Lib")
 #endif
 
 #include "swift/Runtime/Win32.h"

stdlib/public/runtime/SymbolInfo.cpp

@@ -18,6 +18,9 @@
 #include <Windows.h>
 #include <DbgHelp.h>
 #include <psapi.h>
+
+#pragma comment(lib, "DbgHelp.Lib")
+
 #elif SWIFT_STDLIB_HAS_DLADDR
 #include <dlfcn.h>
 #endif