LU-3373 misc: small changes for 3.10 server support

LU-3373 misc: small changes for 3.10 server support

--quota use struct kqid as parameter
--export ext4_dec/inc_count for nlink count
--ext4_find_entry & ext4_journal_start_sb changes
--iop->truncate removed
--other trival changes to calm compiler warning

Lustre-commit: 9bd7e40d2934cd0162eeff5388f054444a982ac9
Lustre-change: http://review.whamcloud.com/7794

Signed-off-by: yang sheng <yang.sheng@intel.com>
Signed-off-by: Bob Glossman <bob.glossman@intel.com>
Signed-off-by: Bobi Jam <bobijam.xu@intel.com>
Reviewed-by: James Simmons <uja.ornl@gmail.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Change-Id: Ia2670d925ecbbfcc1ed3abb1a15a8d91fa27bd32
Reviewed-on: http://review.whamcloud.com/9013
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>