drivers: staging: media: omap4iss: Use BIT macro instead of left shifting

There is a BIT(nr) macro available in Linux Kernel,
which does the same thing.

Example:  1 << 7  is same as BIT(7)

Signed-off-by: Moses Christopher Bollavarapu <mosescb.dev@gmail.com>
Reviewed-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>