can: peak_usb: align CAN channel ID format in log with sysfs attribute

Previously, the CAN channel ID was printed to the kernel log in decimal
upon connecting a new PEAK device. This behavior is inconsistent with
the hexadecimal format of the CAN channel ID sysfs attribute. This patch
updates the log message to output the id in hexadecimal.

Signed-off-by: Lukas Magel <lukas.magel@posteo.net>
Link: https://lore.kernel.org/all/20230116200932.157769-8-lukas.magel@posteo.net
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>