ARM: dts: Reintroduce dual config for CPU on msm8974

Reintroduce the dual configuration mode for CPU masters on msm8974.
This will enable throttling of CPU in certain low bandwidth usecases
to alleviate timeline issues for other real time masters in the SOC.

Change-Id: Ic32f217ce40ee6ead4edd191811f9ce9f4e7e7ce
Signed-off-by: Girish Mahadevan <girishm@codeaurora.org>