Merge branches 'acpi-battery', 'acpi-button' and 'acpi-driver'

Merge additional updates of multiple core ACPI device drivers (battery,
button, video, EC, SMBUS HC) for 7.0-rc1:

 - Drop redundant checks from the ACPI notify handler and the driver
   remove callback in the ACPI battery driver (Rafael Wysocki)

 - Move the creation of the wakeup source during the ACPI button driver
   probe to an earlier point to avoid missing a wakeup event due to a
   race and clean up system wakeup handling and remove callback in that
   driver (Rafael Wysocki)

 - Drop unnecessary driver_data pointer clearing from the ACPI EC and
   SMBUS HC drivers and make the ACPI backlight (video) driver clear the
   device's driver_data pointer on remove (Rafael Wysocki)

* acpi-battery:
  ACPI: battery: Drop redundant checks from acpi_battery_remove()
  ACPI: battery: Drop redundant check from acpi_battery_notify()

* acpi-button:
  ACPI: button: Tweak acpi_button_remove()
  ACPI: button: Tweak system wakeup handling
  ACPI: button: Call device_init_wakeup() earlier during probe

* acpi-driver:
  ACPI: driver: Drop driver_data pointer clearing from two drivers
  ACPI: video: Clear driver_data pointer on remove