[UCRT] Import Microsoft.Windows.SDK.CRTSource version 10.0.22621.3

Imported from https://www.nuget.org/packages/Microsoft.Windows.SDK.CRTSource/10.0.22621.3
License: MIT

sdk/lib/ucrt/string/wcsrev.cpp

@@ -0,0 +1,30 @@
+//
+// wcsrev.cpp
+//
+//      Copyright (c) Microsoft Corporation.  All rights reserved.
+//
+// Defines _wcsrev(), which reverses a wide chraacter string in place.  The
+// pointer to the string is returned.
+//
+#include <string.h>
+
+
+
+extern "C" wchar_t* __cdecl _wcsrev(wchar_t* const string)
+{
+    // Find the end of the string:
+    wchar_t* right = string;
+    while (*right++) { }
+    right -= 2;
+
+    // Reverse the strong:
+    wchar_t* left = string;
+    while (left < right)
+    {
+        wchar_t const c = *left;
+        *left++  = *right;
+        *right-- = c;
+    }
+
+    return string;
+}