media: rc: ati_remote: increase mouse_name buffer size

Fixes this compiler warning:

drivers/media/rc/ati_remote.c: In function 'ati_remote_probe':
drivers/media/rc/ati_remote.c:876:21: warning: ' mouse' directive output may be truncated writing 6 bytes into a region of size between 1 and 80 [-Wformat-truncation=]
  876 |                  "%s mouse", ati_remote->rc_name);
      |                     ^~~~~~
drivers/media/rc/ati_remote.c:875:9: note: 'snprintf' output between 7 and 86 bytes into a destination of size 80
  875 |         snprintf(ati_remote->mouse_name, sizeof(ati_remote->mouse_name),
      |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  876 |                  "%s mouse", ati_remote->rc_name);
      |                  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Reviewed-by: Sean Young <sean@mess.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>