drm/i915: fix intel_backlight_device_register declaration

commit ac29fc66855b79c2960c63a4a66952d5b721d698 upstream.

The alternative intel_backlight_device_register() definition apparently
never got used, but I have now run into a case of i915 being compiled
without CONFIG_BACKLIGHT_CLASS_DEVICE, resulting in a number of
identical warnings:

drivers/gpu/drm/i915/intel_drv.h:1739:12: error: 'intel_backlight_device_register' defined but not used [-Werror=unused-function]

This marks the function as 'inline', which was surely the original
intention here.

Fixes: 1ebaa0b9c2d4 ("drm/i915: Move backlight registration to connector registration")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20171127151239.1813673-1-arnd@arndb.de
(cherry picked from commit 2de2d0b063b08becb2c67a2c338c44e37bdcffee)
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 file changed