LU-4063 tests: use $DIR to check file at agent host

LU-4063 tests: use $DIR to check file at agent host

12a used to use DIR2 which is not mounted at agent host.

Signed-off-by: Jinshan Xiong <jinshan.xiong@intel.com>
Change-Id: I5cea35c5e20f8c1064902d6b116dbddb1096c150
Reviewed-on: http://review.whamcloud.com/7869
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: jacques-Charles Lafoucriere <jacques-charles.lafoucriere@cea.fr>
Reviewed-by: John L. Hammond <john.hammond@intel.com>
Reviewed-by: James Nunez <james.a.nunez@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>