audioflinger: forward device change to effects in direct thread

Device change during offload playback is not informed to effect chain
which causes effects still work on unexpected output devices. Add device
change notification in direct output thread.

Original author wjiang <wjiang@codeaurora.org>

CRs-Fixed: 630408
Bug: 14053172
Signed-off-by: Glenn Kasten <gkasten@google.com>
Change-Id: I094a99bdf540479cee2fca6614ec35c2fa7d6046