dsp: q6adm: Resolve pop noise heard during playback when screen rotated

Pop noise is heard during speaker swap when screen
is rotated. This is because path is not muted before
swap. Mute path before applying swap and unmute afterwards
to resolve issue.

Change-Id: I235a75f92c451b95dae89671681628e500e3029a
Signed-off-by: Vatsal Bucha <vbucha@codeaurora.org>