staging/lustre/hsm: count NULL terminator in hai_zero/hal_size

If fsname is 8-byte aligned, hai_zero fails to count the ending NULL
terminator causing hai to directly attached after fsname and future
hai_zero will return a different position for first hai.

Signed-off-by: Peng Tao <bergwolf@gmail.com>
Reviewed-on: http://review.whamcloud.com/9431
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-4689


Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: Jinshan Xiong <jinshan.xiong@intel.com>
Signed-off-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>