cluster/afr: Turn on eager-lock for fd DATA transactions

Problem:
With the present implementation, eager-lock is issued for
any fd fop. eager-lock is being transferred to metadata
transactions. But the lk-owner is set to local->fd address
only for DATA transactions, but for METADATA transactions
it is frame->root. Because of this unlock on the eager-lock fails
and rebalance hangs.

Fix:
Enable eager-lock for fd DATA transactions

Change-Id: If30df7486a0b2f5e4150d3259d1261f81473ce8a
BUG: 916226
Signed-off-by: Pranith Kumar K <pkarampu@redhat.com>
Reviewed-on: http://review.gluster.org/4588
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Anand Avati <avati@redhat.com>