[PSDK][REACTOS] Fix definitions and usage of DWLP_MSGRESULT, DWLP_DLGPROC, and DWLP_USER

- Make sure the DWLP_* values are correct on _WIN64
- Don't use the DWL_* constants, they are not portable. Enforce this by removing them entirely from winuser.h
- Make sure Get/SetWindowLong*Ptr* is used and pointers are not truncated to LONG

dll/win32/shell32/dialogs/drvdefext.cpp

@@ -460,7 +460,7 @@ CDrvDefExt::GeneralPageProc(
 
                     if (GetDlgItemTextW(hwndDlg, 14000, wszBuf, _countof(wszBuf)))
                         SetVolumeLabelW(pDrvDefExt->m_wszDrive, wszBuf);
-                    SetWindowLongPtr(hwndDlg, DWL_MSGRESULT, PSNRET_NOERROR);
+                    SetWindowLongPtr(hwndDlg, DWLP_MSGRESULT, PSNRET_NOERROR);
                     return TRUE;
                 }
             }