Use the HEAP_WINE_SEGPTR flag to specify allocations on the segptr heap.
Added a hack in MapLS to recognize such allocations and use the heap
selector in this case.

diff --git a/include/winbase.h b/include/winbase.h
index e4a7a6e..31a4738 100644
--- a/include/winbase.h
+++ b/include/winbase.h
@@ -1883,7 +1883,7 @@
 void        WINAPI DisposeLZ32Handle(HANDLE);
 HANDLE      WINAPI DosFileHandleToWin32Handle(HFILE);
 VOID        WINAPI GetpWin16Lock(SYSLEVEL**);
-DWORD       WINAPI MapLS(LPVOID);
+DWORD       WINAPI MapLS(LPCVOID);
 LPVOID      WINAPI MapSL(DWORD);
 VOID        WINAPI ReleaseThunkLock(DWORD*);
 VOID        WINAPI RestoreThunkLock(DWORD);