Initialize Unicode code when generating wxEVT_CHAR_HOOK in wxMSW.

Use the fixed value of 0 for the keys without Unicode equivalent instead of
whatever junk was there in the uninitialized variable.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@73719 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/msw/window.cpp

@@ -6606,7 +6606,7 @@ wxKeyboardHook(int nCode, WORD wParam, DWORD lParam)
     DWORD hiWord = HIWORD(lParam);
     if ( nCode != HC_NOREMOVE && ((hiWord & KF_UP) == 0) )
     {
-        wchar_t uc;
+        wchar_t uc = 0;
         int id = wxMSWKeyboard::VKToWX(wParam, lParam, &uc);
 
         // Don't intercept keyboard entry (notably Escape) if a modal window