staging: lustre: wrong parameter to cfs_hash_keycpy

cfs_hash_rehash_key() passed wrong parameter to cfs_hash_keycpy,
hnode should be the second parameter not the third one.

Signed-off-by: Liang Zhen <liang.zhen@intel.com>
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-4362
Reviewed-on: http://review.whamcloud.com/8509


Reviewed-by: Bobi Jam <bobijam@gmail.com>
Reviewed-by: Johann Lombardi <johann.lombardi@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>