Prior to this commit it was not possible to deactivate the first few
channels of an audio device. If say channel 5 was active in the
requested configuration then all channels up to 5 would be active as
well regardless of the provided activation pattern.

As opposed to the number of hardware output channels.

Xcode 14 has minimum deployment targets of macos 10.13 and iOS 11.

Until this commit CoreAudioIODevice could report inconsistent information in its
getActiveOutputChannels() and getOutputChannelNames() functions, and for
inputs as well. The reason for this was that a sudden configuration change
would immediately be reflected by the CoreAudioInternal::Stream::chanNames
member because those are read in the Stream's constructor. The activeChan
member would however just store stale values, until the Stream was recreated
later during device reopen.

This issue could lead to the AudioPluginHost crashing when opening a
Bluetooth headset.

This fixes an issue where e.g. pressing 'return' to select an item from
an IME list would directly insert a newline character, rather than
selecting the entry.