rfkill: Rename rfkill_any_led_trigger* functions

Rename these functions to rfkill_global_led_trigger*, as they are going
to be extended to handle another global rfkill led trigger.

This commit does not change any functionality.

Signed-off-by: João Paulo Rechi Vita <jprvita@endlessm.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>