clk: qcom: Elaborate on "active" clocks in the RPM clock bindings

- #clock-cells : shall contain 1

The clock enumerators are defined in <dt-bindings/clock/qcom,rpmcc.h>

and come in pairs: FOO_CLK followed by FOO_A_CLK. The latter clock

is an "active" clock, which means that the consumer only care that the

clock is available when the apps CPU subsystem is active, i.e. not

suspended or in deep idle. If it is important that the clock keeps running

during system suspend, you need to specify the non-active clock, the one

not containing *_A_* in the enumerator name.

Example:

	smd {

		compatible = "qcom,smd";