snd_hda: Synchronize DMA buffers for the control path

Make sure both sides of the DMA buffer memory accesses for the CORB and RIRB
(control buffers) in snd_hda (device and CPU) can see coherent memory. This
is needed on weakly ordered architectures including PowerPC and ARM. Patch
originally by mmel, with small changes.

This does not cover the data path of snd_hda. We don't have sync operations
for in-progress DMA buffers, to sync ranges of a map.

Reviewed By: mmel
Differential Revision: https://reviews.freebsd.org/D16517