i2c: octeon: Avoid printk after too long SMBUS message

Remove the warning about a too long SMBUS message because
the ipmi_ssif driver triggers this warning too frequently so it
spams the message log.

Signed-off-by: Jan Glauber <jglauber@cavium.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>