ANDROID: cuttlefish_defconfig: Add support for AC97 audio

Enable driver support for the ac97 emulation provided by QEMU and
crosvm. This is for the older 'ac97' soundhw, not 'hda'.

Bug: 120439617
Bug: 126955561
Test: local build and test of sound from cuttlefish
Change-Id: I6c29e352e0be161e2a1dc35fde50b888b7dbf86e
Signed-off-by: Alistair Strachan <astrachan@google.com>