CSD: rename get/setOutputRs2 to include upper bound

RS2 represents an interval of power levels. This is why it is clearer to
specify upper bound in the naming to make it clear that we refer to the
upper limit which when exceeded will trigger a momentary exposure.

Test: atest SoundDoseHelperTest
Bug: 273961110
Change-Id: Ib1bf8258e064c6e421d71e7269637522a6411145