LU-7004 tests: move from lctl conf_param to lctl set_param -P

LU-7004 tests: move from lctl conf_param to lctl set_param -P

To ensure that the work to make lctl set_param -P functional
we need to provide a way to test either lctl conf_param or
lctl set_param -P in the test suite.

Change-Id: I2f58a9b5262eed03ddc3a2ff15ac96b752d97735
Signed-off-by: James Simmons <uja.ornl@yahoo.com>
Reviewed-on: https://review.whamcloud.com/30087
Tested-by: Jenkins
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Ben Evans <bevans@cray.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>