i2c: synquacer: fix fence-post error in retry loop

There is a difference between attempts and retries.

Signed-off-by: Peter Rosin <peda@axentia.se>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>