ASOC: msm: allocate buf pointer only if session is valid

The event handler may get events even if the buffer is
deallocated already. The access to buff should be done only if
its not deallocated and session valid.

Change-Id: I3eac5976db354612cb5550acc2bb67396c8c47fe
CRs-fixed: 311574
Signed-off-by: Asish Bhattacharya <asishb@codeaurora.org>
1 file changed