drm/bridge: ptn3460: Include linux/gpio/consumer.h

drm/bridge: ptn3460: Include linux/gpio/consumer.h

If GPIOLIB=n and asm-generic/gpio.h is not used:

    drivers/gpu/drm/bridge/ptn3460.c: In function ‘ptn3460_pre_enable’:
    drivers/gpu/drm/bridge/ptn3460.c:135: error: implicit declaration of function ‘gpiod_set_value’
    drivers/gpu/drm/bridge/ptn3460.c: In function ‘ptn3460_probe’:
    drivers/gpu/drm/bridge/ptn3460.c:333: error: implicit declaration of function ‘devm_gpiod_get’
    drivers/gpu/drm/bridge/ptn3460.c:333: warning: assignment makes pointer from integer without a cast
    drivers/gpu/drm/bridge/ptn3460.c:340: error: implicit declaration of function ‘gpiod_direction_output’
    drivers/gpu/drm/bridge/ptn3460.c:346: warning: assignment makes pointer from integer without a cast

Add the missing #include <linux/gpio/consumer.h> to fix this.

Fixes: af478d8823 ("drm/bridge: ptn3460: use gpiod interface")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: David Airlie <airlied@linux.ie>
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: Thierry Reding <treding@nvidia.com>