staging: most: i2c: remove empty callback request_netinfo

Since the networking-aim checks the availability of the callback
request_netinfo, this patch removes the empty callback request_netinfo
from the i2c-hdm.

Signed-off-by: Andrey Shvetsov <andrey.shvetsov@k2l.de>
Signed-off-by: Christian Gromm <christian.gromm@microchip.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>