sunxi: twi: Enable clocks on sun7i

sunxi: twi: Enable clocks on sun7i

Commit 6c739c5d added code to enable i2c bus 4 and 5 on the sun7i SoC
but forgot to extend the range check in clock_twi_onoff, resulting in
the clock not getting enabled.

The range-check is not needed at all, since clock_twi_onoff only gets
called with such high indexes when CONFIG_I2C3_ENABLE / CONFIG_I2C4_ENABLE
is set and Kconfig already only allows these on sun6i / sun7i.

This commit removes the range-check all together fixing i2c bus 4 and 5
not working on sun7i.

Signed-off-by: Olliver Schinagl <o.schinagl@ultimaker.com>
[hdegoede@redhat.com] Remove range check instead of extending it
Signed-off-by: Hans de Goede <hdegoede@redhat.com>