media: am437x: don't fill in bus_info

Let the V4L2 core fill this in.

This fixes this warning:

drivers/media/platform/ti/am437x/am437x-vpfe.c: In function 'vpfe_querycap':
drivers/media/platform/ti/am437x/am437x-vpfe.c:1279:35: warning: '%s' directive output may be truncated writing up to 35 bytes into a region of size 23 [-Wformat-truncation=]
 1279 |                         "platform:%s", vpfe->v4l2_dev.name);
      |                                   ^~
drivers/media/platform/ti/am437x/am437x-vpfe.c:1278:9: note: 'snprintf' output between 10 and 45 bytes into a destination of size 32
 1278 |         snprintf(cap->bus_info, sizeof(cap->bus_info),
      |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 1279 |                         "platform:%s", vpfe->v4l2_dev.name);
      |                         ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Reviewed-by: Lad Prabhakar <prabhakar.csengg@gmail.com>