media: v4l2-subdev.h: BIT() is not available in userspace

The BIT macro is not available in userspace, so replace BIT(0) by
0x00000001.

Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Fixes: 6446ec6c ("media: v4l2-subdev: add VIDIOC_SUBDEV_QUERYCAP ioctl")
Cc: <stable@vger.kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>