Add LE audio broadcast dynamic switch feature

If the device set ro.bluetooth.leaudio_broadcast_switcher.supported=true
and the hardware supports le audio required capabilities, the feature
could be switched via developer option

Bug: 236907310

Test: switch LE audio feature, and check LE audio functionality status
Change-Id: I2e5c4cdce2c2b52ae7bd696cf7752410d995d228