Staging: media: remove useless dev_info to avoid null ptr dereference

Context is used in dev_info after it has been freed.
This patch fix that issue by removing the dev_info itself,
for msg doesn't look much necessary.

Signed-off-by: Haneen Mohammed <hamohammed.sa@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>