features/marker: Filter internal xattrs in lookup

        Backport of http://review.gluster.org/9061

Afr should ignore quota-size-key as part of self-heal
but should heal quota-limit key.

BUG: 1163569
Change-Id: I93d203002eac4fe20b70730c27c852d783c16d7f
Signed-off-by: Pranith Kumar K <pkarampu@redhat.com>
Reviewed-on: http://review.gluster.org/9110
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Vijay Bellur <vbellur@redhat.com>