Bluetooth: btmrv: Use %*ph specifier instead of print_hex_dump_bytes

Use standard print specifier and remove print_hex_dump_bytes call.
Makes output more sensible:

...
[18809.401218] 00000000: 0b 00 00 fe 5b fc 01 f2 00 00 00    ....[......
...

would be changed to

...
[18809.401218] Bluetooth: hex: 0b 00 00 fe 5b fc 01 f2 00 00 00
...

Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>