media: imx: utils: Enclose IMX_BUS_FMTS macro in parenthesis

Conform to kernel coding style by wrapping macro in parenthesis. Issue
found by checkpatch.

Signed-off-by: Angel Alberto Carretero <angelalbertoc.r@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>