It appears calling GetFileInformationByHandleEx with
FILE_ATTRIBUTE_TAG_INFO fails on FAT file system. FAT does not
support symlinks, so assume there are no symlnks when
GetFileInformationByHandleEx returns ERROR_INVALID_PARAMETER.

Fixes #29214

Change-Id: If2d9f3288bd99637681ab5fd4e4581c77b578a69
Reviewed-on: https://go-review.googlesource.com/c/154377
Run-TryBot: Alex Brainman <alex.brainman@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>