i2c_recv() cannot fail, so there is no need to check the return
value. It also returns unt8_t, so comparing with < 0 is not
meaningful.
Fix up various I2C controllers to remove the unneeded code.
Signed-off-by: Corey Minyard <cminyard@mvista.com>
Suggested-by: Peter Maydell <peter.maydell@linaro.org>