CSD: Add support for csd feature flag

Add the possibility to enable/disable the calculation of sound dose
through the enable_csd flag. This can be interesting for possible
experiments with the droidfood population to assess if we can enable
CSD in the US too (the US is currently disabled by the MCC logic).

Test: enable/disable CSD with mobdog
Bug: 276884465
Change-Id: I7cd70196d6558fd2c5b52dd8e350837904f51829