ALSA: ASoC: pxa: fix pxa2xx-ac97 DAI initialization order

After recent changes to codec/DAI initialization order changes, codec
driver (wm9712 in my case) tries to access codec prior to
pxa2xx_ac97_hw_probe() being called (because DAIs are probed after all
codecs are probed). Move hw-related probe/remove/suspend/resume
functions to pxa2xx-ac97 driver level, instead of DAI level.

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Signed-off-by: Mark Brown <broonie@linaro.org>