Add debug system properties to control profiling limits.

When security.perf_harden is disabled through adb, use some debug
system properties to set profiling limits in the kernel, including
cpu percentage, memory, and max sample rate.

Bug: 110706031
Test: boot hikey960 and manually set system properties to make
Test: sure it works.

Change-Id: I44c0adf3a000bb393905233f2a097c97b5fe91ec