[SHLWAPI] Import Wine commit c8175e6c7a7 (Fix Stat() method for file streams) by Nikolay Sivov.

Fixes crash in shlwapi_winetest:istream.

dll/win32/shlwapi/istream.c

···
 
     TRACE("(%p,%p,%d)\n", This, lpStat, grfStatFlag);
 
-    if (!grfStatFlag)
+    if (!lpStat)
         return STG_E_INVALIDPOINTER;
 
     memset(&fi, 0, sizeof(fi));