Set mAllowNonNativeRefreshRateOverride to true

We will only send non-native refersh rate override config for
gamedashboard. So we can make sure that SurfaceFlinger sends
the correct override list.

- Set mAllowNonNativeRefreshRateOverride to true by default

Bug: b/218534715, b/222135867
Test: atest DisplayManagerServiceTest
      atest FrameRateOverrideHostTest

Change-Id: Ic9cd4802e221144319e83d79fc422b5c3cb61a86