This patch adds some common helper functions like translating dsp error
to linux error codes and channel mappings etc.

These functions are used in all the following qdsp6 drivers.
Signed-off-by: NSrinivas Kandagatla <srinivas.kandagatla@linaro.org>
Reviewed-and-tested-by: NRohit kumar <rohitkr@codeaurora.org>
Reviewed-by: NBanajit Goswami <bgoswami@codeaurora.org>
Signed-off-by: NMark Brown <broonie@kernel.org>