Further template BlockDecimator by element type, use for audio buffer.

Appropriating for use as a buffer accumulator that will save up enough audio samples to put into an audio DMA buffer.

firmware/baseband/audio_output.cpp

@@ -57,6 +57,17 @@ void AudioOutput::write(
 
 void AudioOutput::write(
 	const buffer_f32_t& audio
+) {
+	block_buffer.feed(
+		audio,
+		[this](const buffer_f32_t& buffer) {
+			this->on_block(buffer);
+		}
+	);
+}
+
+void AudioOutput::on_block(
+	const buffer_f32_t& audio
 ) {
 	const auto audio_present_now = squelch.execute(audio);