Linux 4.5: no highmem in symlink ops

Linux 4.5: no highmem in symlink ops

Symlink bodies in the pagecache should not be in highmem, as
upstream converted in commit 21fc61c73.

Reviewed-on: https://gerrit.openafs.org/12264
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Joe Gorse <jhgorse@gmail.com>
Tested-by: Joe Gorse <jhgorse@gmail.com>
Reviewed-by: Benjamin Kaduk <kaduk@mit.edu>
(cherry picked from commit d9cfc1f3f5a75f1dbb14a56cd3da9db6b7a48065)

Change-Id: If1ef28955b08db4d95d6bd8a3b833895243f858a
Reviewed-on: https://gerrit.openafs.org/12300
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Stephan Wiesand <stephan.wiesand@desy.de>
Tested-by: Stephan Wiesand <stephan.wiesand@desy.de>