ASoc: msm: qdsp6v2: Fix for NULL check

- Required check added for NULL pointer

Signed-off-by: Mingming Yin <mingming@codeaurora.org>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>