posix:  Changed order of chown and chmod

    Problem:
    Rebalance process runs in the root mode. If a normal
    user create a file and if it  requires migration then
    because the migrated file is created by root, its owner and
    mode should  be changed to the source normal user and
    permission should be changed the previous mode. If
    the suid bit is also set, then at the destination
    suid bit should also be set.

    Two operations are performed in the given order:
    1. chmod
    2. chown

    But chown resets the suid bit. So changed the order
    of these two operations so that first chown will be
    performed and then chmod will be performd so that
    suid bit will be preserved.

Change-Id: Ib63b5cf528f8336b69bf090ad43bb02eec1d1602
BUG: 1086228
Signed-off-by: Venkatesh Somyajulu <vsomyaju@redhat.com>
Reviewed-on: http://review.gluster.org/7435
Reviewed-by: Niels de Vos <ndevos@redhat.com>
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Vijay Bellur <vbellur@redhat.com>