Add ARM common idle state device bindings for cpuidle support for APQ
8064.

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