LU-1526 tests: Handle OFD procfs changes

In order to interop with 2.4 server, the following procfs entry
changes need to be handled:

- obdfilter.*.mntdev -> osd-*.*.mntdev
- obdfilter.*.<cache_related> -> osd-*.*.<cache_related>

Test-Parameters: envdefinitions=SLOW=yes,ENABLE_QUOTA=yes clientarch=x86_64 serverarch=x86_64 testlist=lfsck,sanity
Signed-off-by: Yu Jian <yujian@whamcloud.com>
Change-Id: I74bfaa1e6d68203951de31676f23fbd8250ec652
Reviewed-on: http://review.whamcloud.com/4958
Reviewed-by: Li Wei <wei.g.li@intel.com>
Tested-by: Hudson
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Tested-by: Maloo <whamcloud.maloo@gmail.com>