ACPI / documentation: fix a sentence about GPIO resources

The sentence "These resources are used be used to pass ..." contains
a suspicious repetition, likely the author meant "These resources can
be used to pass ...".

Simplify the wording.

Signed-off-by: Antonio Ospite <ao2@ao2.it>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>