These header file should not be included in other header files. Remove
them and add to each individual file. Add test/test.h to test/ui.h since
that is a reasonable place.
Signed-off-by: Simon Glass <sjg@chromium.org>
The i2s bus is commonly used with audio codecs. It provides a way to
stream digital data sychronously in both directions. U-Boot only supports
audio output, so this uclass is very simple, with a single tx_data()
method.
Add a uclass and a test for i2s.
Signed-off-by: Simon Glass <sjg@chromium.org>