media-add-ons/mixer: Fix 'new[]' array freed with 'delete'

fMixBufferChannelTypes is allocated by new[] in _ApplyOutputFormat(),
but freed by delete.
Pointed out by LGTM.

Change-Id: I07b85801e0103094c5751306ea2c50ca9354ddb9
Reviewed-on: https://review.haiku-os.org/c/haiku/+/1877
Reviewed-by: Axel Dörfler <[email protected]>

src/add-ons/media/media-add-ons/mixer/MixerCore.cpp

@@ -112,7 +112,7 @@ MixerCore::~MixerCore()
 		delete[] fResampler;
 	}
 
-	delete fMixBufferChannelTypes;
+	delete[] fMixBufferChannelTypes;
 }
 
 
@@ -429,7 +429,7 @@ MixerCore::_ApplyOutputFormat()
 	if (fMixBuffer != NULL)
 		rtm_free(fMixBuffer);
 
-	delete fMixBufferChannelTypes;
+	delete[] fMixBufferChannelTypes;
 
 	fMixBufferFrameRate = (int32)(0.5 + format.frame_rate);
 	fMixBufferFrameCount = frames_per_buffer(format);