staging: lustre: libcfs: add parens around macros args

One may call 'CFS_FAIL_TIMEOUT(id, secs + 5);' and get unexpected result
after macro substitution, viz., 'secs + 5' will turn into
'secs + 5 * 1000'

Signed-off-by: Ivan Bornyakov <brnkv.i1@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>