imx233: make sure clk_io is running at top speed

Change-Id: Ie6be98df72eaf31129224af3b295037e7cf74a19
imx233: fix ssp

In case of timeouts or other errors, the dma is blocked and the
error irq is triggered. With the old code, that would result into
a 1s timeout, which is obviously bad, so fix the code to stop as
soon as possible.

Change-Id: I06c3a030576434d3e65f9800caa4e7788ded7880