LU-550 incorrect quota hash function

LU-550 incorrect quota hash function

Quota code uses 'uid' or '(1 << 32) + gid' as the hash key, however,
the quota hash function lqs_hash() always try to interpret such a
unsigned long long key as a 'quota_adjust_qunit' struct, then calculate
the hash value by quota_adjust_qunit->qaq_id.

Signed-off-by: Niu Yawei <niu@whamcloud.com>
Change-Id: I128f2835ff590d712b0a1641af7361146e8e3e81
Reviewed-on: http://review.whamcloud.com/1163
Tested-by: Hudson
Reviewed-by: Fan Yong <yong.fan@whamcloud.com>
Reviewed-by: Johann Lombardi <johann@whamcloud.com>