Bluetooth: Fix boolean logic in quiet mode enable

* Change If97c454a8e5aff34c4f8550f7ade3da413a200b7 introduced a bug that
  flipped the logic of quiet mode enable in the handler for
  MESSAGE_BLUETOOTH_SERVICE_CONNECTED, causing quiet mode to be enabled
  when toggling from Settings and system UI.

Bug: 70395489
Test: make, toggle bluetooth on/off
Change-Id: I405fb462783df0d52d9ce84d2ebe959e56a1aa30