Fix broken SpinLock.

The SpinLock was all backwards and didn't actually work. Fixing it exposed
how wrong most of the locking here is.

I need to come up with a better granularity here.

Kernel/kprintf.cpp

@@ -1,10 +1,11 @@
 #include "kprintf.h"
 #include "Console.h"
+#include "IO.h"
 #include <stdarg.h>
 #include <AK/Types.h>
 #include <AK/printf.cpp>
 
-static void console_putch(char*, char ch)
+static void console_putch(char*&, char ch)
 {
     Console::the().write((byte*)&ch, 1);
 }
@@ -32,3 +33,17 @@ int ksprintf(char* buffer, const char* fmt, ...)
     va_end(ap);
     return ret;
 }
+
+static void debugger_putch(char*&, char ch)
+{
+    IO::out8(0xe9, ch);
+}
+
+int dbgprintf(const char* fmt, ...)
+{
+    va_list ap;
+    va_start(ap, fmt);
+    int ret = printfInternal(debugger_putch, nullptr, fmt, ap);
+    va_end(ap);
+    return ret;
+}