setupapi: Fix parsing of UCS-16 files.

Fix parsing of UCS-16 files prefixed with the Unicode BOM. Based on a 
patch by Hervé Poussineau.
diff --git a/dlls/setupapi/parser.c b/dlls/setupapi/parser.c
index e6587c7..514e85a 100644
--- a/dlls/setupapi/parser.c
+++ b/dlls/setupapi/parser.c
@@ -967,7 +967,14 @@
             HeapFree( GetProcessHeap(), 0, new_buff );
         }
     }
-    else err = parse_buffer( file, buffer, (WCHAR *)((char *)buffer + size), error_line );
+    else
+    {
+        WCHAR *new_buff = (WCHAR *)buffer;
+        /* UCS-16 files should start with the Unicode BOM; we should skip it */
+        if (*new_buff == 0xfeff)
+            new_buff++;
+        err = parse_buffer( file, new_buff, (WCHAR *)((char *)buffer + size), error_line );
+    }
 
     if (!err)  /* now check signature */
     {