EX-3002 lipe: lpurge units

EX-3002 lipe: lpurge units

Use kb suffixes consistently in lpurge. Add loa_used_kb() to
encapsulate the poor naming otf the loa_blocks member in struct
lipe_object_attrs. Remove some misleading comments. Rename structure
members lo_blocks to lo_used_kb, and ls_*_space to ls_*_used_kb. In
lpurge_purge_slot() rename target to target_kb, and total to
queued_kb. Rename lpurge_free_space() to lpurge_purge().

Signed-off-by: John L. Hammond <jhammond@whamcloud.com>
Test-Parameters: trivial testlist=hot-pools
Change-Id: I0bbd4f0ea815e3a95eb36d1dc590f03f76eeccd3
Reviewed-on: https://review.whamcloud.com/45388
Reviewed-by: Jian Yu <yujian@whamcloud.com>
Reviewed-by: Alexandre Ioffe <aioffe@ddn.com>
Tested-by: Maloo <maloo@whamcloud.com>
Tested-by: jenkins <devops@whamcloud.com>
Reviewed-by: Alex Zhuravlev <bzzz@whamcloud.com>
Reviewed-on: https://review.whamcloud.com/46125