interconnect: sdm660: merge common code into icc-rpm

Other RPM interconnect drivers might also use QoS support. Move AP-owned
nodes support from SDM660 driver to common icc-rpm.c.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@somainline.org>
Tested-by: Marijn Suijten <marijn.suijten@somainline.org>
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Link: https://lore.kernel.org/r/20210903232421.1384199-5-dmitry.baryshkov@linaro.org


Signed-off-by: Georgi Djakov <djakov@kernel.org>