Kernel: First cut of a sb16 driver

Also add an AudioServer that (right now) doesn't do much.
It tries to open, parse, and play a wav file. In the future, it can do more.

My general thinking here here is that /dev/audio will be "owned" by AudioServer,
and we'll do mixing in software before passing buffers off to the kernel
to play, but we have to start somewhere.

Kernel/init.cpp

@@ -16,6 +16,7 @@
 #include <Kernel/Devices/MBRPartitionTable.h>
 #include <Kernel/Devices/NullDevice.h>
 #include <Kernel/Devices/PS2MouseDevice.h>
+#include <Kernel/Devices/SB16.h>
 #include <Kernel/Devices/RandomDevice.h>
 #include <Kernel/Devices/SerialDevice.h>
 #include <Kernel/Devices/ZeroDevice.h>
@@ -39,6 +40,7 @@ VirtualConsole* tty2;
 VirtualConsole* tty3;
 KeyboardDevice* keyboard;
 PS2MouseDevice* ps2mouse;
+SB16* sb16;
 DebugLogDevice* dev_debuglog;
 NullDevice* dev_null;
 SerialDevice* ttyS0;
@@ -177,6 +179,7 @@ extern "C" [[noreturn]] void init()
 
     keyboard = new KeyboardDevice;
     ps2mouse = new PS2MouseDevice;
+    sb16 = new SB16;
     dev_null = new NullDevice;
     ttyS0 = new SerialDevice(SERIAL_COM1_ADDR, 64);
     ttyS1 = new SerialDevice(SERIAL_COM2_ADDR, 65);