ASoC: mdmcalifornium: Add fix for machine driver probe failure

Add a dummy device to ensure that a platform driver gets
registered once ADSP is up. This make sure that the deffered
codec driver gets probed. This is occurring due to a race
condition where all the devices are registered before ADSP is up.

CRs-fixed: 1032883
Change-Id: I72184f18142daf9584318e2e64d661b08742e036
Signed-off-by: Josh Kirsch <jkirsch@codeaurora.org>