media: ti-vpe: cal: Use correct device name for bus_info

The v4l2_capability bus_info field, filled by the VIDIOC_QUERYCAP ioctl
handler, specifies the location of the device in the system. For
platform devices, V4L2 specifies that the value must be "platform:"
followed by the device name. Fix the cal_querycap() function to set the
right value.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Reviewed-by: Benoit Parrot <bparrot@ti.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>