busybox

i2cdetect: add a check for (mode == DETECT_MODE_AUTO)

We should only warn the user about addresses to be skipped if
(mode == DETECT_MODE_AUTO).

Signed-off-by: Bartosz Golaszewski <bartekgola@gmail.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>