Add audio/ sub-syste, include/nuttx/audio.h interface, and drivers/audio/vs1053.c driver to NuttX. From Ken Pettit

audio/Kconfig

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+#
+# For a description of the syntax of this configuration file,
+# see misc/tools/kconfig-language.txt.
+#
+
+config AUDIO
+	bool "Audio Support"
+	default n
+	---help---
+		Enables overall support for Audio library.
+
+if AUDIO
+
+config AUDIO_NCHANNELS
+	int "Number of Audio Channels"
+	default 2
+	---help---
+		Stereo channel support is standard, but some systems may support 5 or 7
+		channel capability.
+
+config AUDIO_LARGE_BUFFERS
+	bool "Support Audio Buffers with greater than 65K samples"
+	default n
+	---help---
+		By default, the Audio Pipeline Buffer uses a 16-bit max sample count, limiting
+		the number of samples per buffer to 65K.  Enable this option to specify a
+		32-bit max sample count for increased samples / buffer capability.
+		channel capability.
+
+menu "Supported Audio Formats"
+
+config AUDIO_FORMAT_PCM
+	bool "PCM Audio"
+	default y
+	---help---
+		Build in support for PCM Audio format.
+
+config AUDIO_FORMAT_MP3
+	bool "MPEG 3 Layer 1"
+	default n
+	---help---
+		Build in support for MP3 Audio format.
+
+config AUDIO_FORMAT_WMA
+	bool "WMA Format (see copyright notice)"
+	default n
+	---help---
+		Add in support for Microsoft Windows Media format.
+
+config AUDIO_FORMAT_OGG_VORBIS
+	bool "Ogg Vorbis format"
+	default n
+	---help---
+		Build in support for the Open Source Ogg Vorbis format.
+
+endmenu
+
+# These are here as placeholders of what could be added 
+
+if CONFIG_AUDIO_PLANNED
+
+config AUDIO_MIXER
+	bool "Planned - Enable support for the software based Audio Mixer"
+	default n
+	---help---
+		The Audio mixer is a software-only based component that can be used
+		to perform audio channel or device mixing.
+
+config AUDIO_MIDI_SYNTH
+	bool "Planned - Enable support for the software-based MIDI synthisizer"
+	default n
+	---help---
+		Builds a simple MIDI synthisizer.
+
+config AUDIO_OUTPUT_JACK_CONTROL
+	bool "Planned - Enable support for output jack control"
+	default n
+	---help---
+		Builds a simple MIDI synthisizer.
+
+config AUDIO_FONT
+	bool "Planned - Enable support for the Audio Font"
+	default n
+	---help---
+		The Audio font provides common audio symbols.
+
+endif
+
+endif