can: peak_usb: add peak_usb_netif_rx() new function

Add a common function that pushes the skb in the network queue with adding
timestamps information, converted from time values read from the
PEAK USB adapters.

Signed-off-by: Stephane Grosjean <s.grosjean@peak-system.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>