uapi: sound: add new ready packet type

There is a chance that the user space can send commands to wdsp
before transport layer is ready to use. Avoid this scenario by
adding a new API which user space can invoke to check the status
of the transport layer before sending any commands.

Change-Id: Icf2af8ddac3925fe02b2c8b7b8767a2141922203
Signed-off-by: Vidyakumar Athota <vathota@codeaurora.org>
Signed-off-by: Nagaradhesh Yeleswarapu <nagaradh@qti.qualcomm.com>