Fixes the following W=1 kernel build warning(s):

 drivers/acpi/nvs.c:94: warning: Function parameter or
  member 'start' not described in 'suspend_nvs_register'
 drivers/acpi/nvs.c:94: warning: Function parameter or
  member 'size' not described in 'suspend_nvs_register'
Signed-off-by: NBaokun Li <libaokun1@huawei.com>
[ rjw: Subject edits ]
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>