ASoC: msm: qdsp6v2: Change incall recording to be session based

In current design, recording will be enabled for all the sessions.
When multi sims are supported, recording will be started only on
active session.
Refactor incall recording function to start and stop recording on
a specific session.
Add mixer control to set session vsid.

Change-Id: I38bb0d80f812755d2eadb132e7aced3599d2a142
Signed-off-by: Helen Zeng <xiaoyunz@codeaurora.org>