platform/chrome: Use imperative mood for ChromeOS ACPI sysfs ABI descriptions

The current descriptions all begin with ("This file shows something")
clause, which is incorrect wording since these mean return value from
sysfs.

Use imperative mood ("Returns something") instead, in line with
corresponding ACPI documentation at firmware-guide/.

Cc: Benson Leung <bleung@google.com>
Cc: Guenter Roeck <groeck@chromium.org>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Cc: Muhammad Usama Anjum <usama.anjum@collabora.com>
Cc: Tzung-Bi Shih <tzungbi@kernel.org>
Cc: Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Cc: Linux Next Mailing List <linux-next@vger.kernel.org>
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Reviewed-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
Link: https://lore.kernel.org/r/20220518083524.37380-3-bagasdotme@gmail.com