LU-15356 tests: get rid of extra spaces in PERM_CMD

LU-15356 tests: get rid of extra spaces in PERM_CMD

The tests use the PERM_CMD set to "set_param  -P" with
extra space before -P" fail because they do not expect
these allowable extra spaces:
   [[ $PERM_CMD = *"set_param -P"* ]]

Fixes: b9c359a70d ("LU-7004 tests: move from lctl conf_param to lctl set_param -P")
Signed-off-by: Elena Gryaznova <elena.gryaznova@hpe.com>
Change-Id: Ia18e32baa56b7dac1f4e15777bfcc4b9ab1048fb
Reviewed-on: https://review.whamcloud.com/45813
Tested-by: jenkins <devops@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: James Simmons <jsimmons@infradead.org>
Reviewed-by: Oleg Drokin <green@whamcloud.com>