storage/posix: Filter out generation number xattr.
storage/posix: Filter out generation number xattr.

Don't return the generation number xattr "trusted.<volname>.gen"
in getxattr, since this can cause replicate self-heal to copy
it over to another subvolume.

Signed-off-by: Vikas Gorur <vikas@gluster.com>
Signed-off-by: Anand V. Avati <avati@dev.gluster.com>

BUG: 315 (generation number support)
URL: http://bugs.gluster.com/cgi-bin/bugzilla3/show_bug.cgi?id=315

Kaushikbv/Gluster,Kaushikbv/Gluster,Kaushikbv/Gluster