staging: lustre: ptlrpc: remove whitespace before a newline

Fix the following type of checkpatch warning:
WARNING: unnecessary whitespace before a quoted newline

Signed-off-by: Kristina Martsenko <kristina.martsenko@gmail.com>
Reviewed-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>