LU-12160 osd-ldiskfs: use-after-free in osd_object_delete()

LU-12160 osd-ldiskfs: use-after-free in osd_object_delete()

store a local copy of projid to avoid use-after-free.

Fixes: 39f63cf54c62 ("LU-4017 quota: add setting/getting project id function")

Change-Id: I60e19de3485cae3df1cc2e8aae6eeed4b5de3a11
Signed-off-by: Alex Zhuravlev <bzzz@whamcloud.com>
Reviewed-on: https://review.whamcloud.com/34596
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Wang Shilong <wshilong@ddn.com>
Tested-by: Jenkins
Reviewed-by: Patrick Farrell <pfarrell@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>