LU-12358 pcc: add project quota support on PCC backend

LU-12358 pcc: add project quota support on PCC backend

Current PCC can enforce a quota limitation of the capacity usage
for each user and group to provide cache isolation. An
administrator can specify the quota enforcement on the local PCC
file system.

Users can perform PCC-cached I/O on files until they receive a
return value -ENOSPC of -EDQUOT, which means that they hit the
quota limit or that there is no free capacity left on the local
PCC backend fs during I/O or the attach process. At this time,
I/O will fall back to the normal I/O path.

This patch adds projecct quota on the PCC backend file system
along with user/group quota.

With this feature, it can have multiple PCC backends on a single
client with different caching rules, so we can define upfront how
much of the client FS can be used for each cache.

Signed-off-by: Qian Yingjin <qian@ddn.com>
Change-Id: Ib93da953d4a3a7091f62094f8175bde91e819895