ASoC: msm: qdsp6v2: handle AFE memory map/unmap failure

In cases where AFE memory map and unmap call fails, return proper
error code and return. This will let the upper layer know about the
map/unmap failure.

Change-Id: Id56691d688285f251848ef76158458e593e5dd2f
Signed-off-by: Banajit Goswami <bgoswa@codeaurora.org>