defconfig: sdm670: Enable Energy-aware scheduler (EAS)

The Energy-aware scheduler (EAS) maximizes the performance
and energy efficiency by selecting the optimal CPUs for
tasks to run.

This config is enabled in perf variant of SDM670 but not in
the debug variant.

Change-Id: Ia789a9496184876accc056f8329a556bbececc8d
Signed-off-by: Pavankumar Kondeti <pkondeti@codeaurora.org>