Add ARM common idle states device bindings for cpuidle support for APQ
8974/8074.

Support Standalone power collapse (SPC) idle state (power down that does
not affect any SoC idle states) for each cpu.
Signed-off-by: NLina Iyer <lina.iyer@linaro.org>
Signed-off-by: NKumar Gala <galak@codeaurora.org>
Signed-off-by: NOlof Johansson <olof@lixom.net>