CP StationaryThrottling bugfixes from SC QPR1

Somehow these fixes were never merged into main (although the test
changes were? Very strange). Merge this fix which eliminates wasted
power from registering the SMD when not necessary.

Bug: 279879297
Test: atest StationaryThrottlingLocationProviderTest
Change-Id: I923573cd5e4735c74d896c4f16210ce62013e2fe