i2c-octeon: Return -ETIMEDOUT in octeon_i2c_wait() on timeout

It doesn't make sense to set result to -ETIMEDOUT but return 0 (success)
afterwards. Since there's code in octeon_i2c_start() to handle the
error, it should be called.

Signed-off-by: Bernhard Walle <walle@corscience.de>
Acked-by: David Daney <ddaney@caviumnetworks.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>