greybus: protocol: make protocol-lookup error message more informative

Make protocol lookup error more informative, by moving it to
gb_connection_bind_protocol and using dev_err.

Also make sure to use hex format for the protocol id as that is what is
used everywhere else.

Signed-off-by: Johan Hovold <johan@hovoldconsulting.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>