Haydn: Part 1 (#2007)

* Haydn: Part 1

Based on my reverse of audio 11.0.0.

As always, core implementation under LGPLv3 for the same reasons as for Amadeus.

This place the bases of a more flexible audio system while making audout & audin accurate.

This have the following improvements:
- Complete reimplementation of audout and audin.
- Audin currently only have a dummy backend.
- Dramatically reduce CPU usage by up to 50% in common cases (SoundIO and OpenAL).
- Audio Renderer now can output to 5.1 devices when supported.
- Audio Renderer init its backend on demand instead of keeping two up all the time.
- All backends implementation are now in their own project.
- Ryujinx.Audio.Renderer was renamed Ryujinx.Audio and was refactored because of this.

As a note, games having issues with OpenAL haven't improved and will not
because of OpenAL design (stopping when buffers finish playing causing
possible audio "pops" when buffers are very small).

* Update for latest hexkyz's edits on Switchbrew

* audren: Rollback channel configuration changes

* Address gdkchan's comments

* Fix typo in OpenAL backend driver

* Address last comments

* Fix a nit

* Address gdkchan's comments

Ryujinx.Audio.Renderer/Server/Voice/VoiceChannelResource.cs

@@ -1,57 +0,0 @@
-//
-// Copyright (c) 2019-2021 Ryujinx
-//
-// This program is free software: you can redistribute it and/or modify
-// it under the terms of the GNU Lesser General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-//
-// This program is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-// GNU Lesser General Public License for more details.
-//
-// You should have received a copy of the GNU Lesser General Public License
-// along with this program.  If not, see <https://www.gnu.org/licenses/>.
-//
-
-using Ryujinx.Common.Memory;
-using System.Runtime.InteropServices;
-
-namespace Ryujinx.Audio.Renderer.Server.Voice
-{
-    /// <summary>
-    /// Server state for a voice channel resource.
-    /// </summary>
-    [StructLayout(LayoutKind.Sequential, Size = 0xD0, Pack = Alignment)]
-    public struct VoiceChannelResource
-    {
-        public const int Alignment = 0x10;
-
-        /// <summary>
-        /// Mix volumes for the resource.
-        /// </summary>
-        public Array24<float> Mix;
-
-        /// <summary>
-        /// Previous mix volumes for resource.
-        /// </summary>
-        public Array24<float> PreviousMix;
-
-        /// <summary>
-        /// The id of the resource.
-        /// </summary>
-        public uint Id;
-
-        /// <summary>
-        /// Indicate if the resource is used.
-        /// </summary>
-        [MarshalAs(UnmanagedType.I1)]
-        public bool IsUsed;
-
-        public void UpdateState()
-        {
-            Mix.ToSpan().CopyTo(PreviousMix.ToSpan());
-        }
-    }
-}