feat: formatter and oslog()

Kernel/Source/OS/Log.c

@@ -0,0 +1,15 @@
+#include <OS/Log.h>
+#include <Lib/String.h>
+#include <Lib/VAArgs.h>
+#include <IO/Serial.h>
+
+void OSLog(const ASCII* format, ...) {
+    ASCII buffer[kOSLogBufferSize];
+   
+    va_list args;
+    va_start(args, format);
+    StringFormatVariadic(buffer, kOSLogBufferSize, format, args);
+    va_end(args);
+
+    IOSerialPutString(buffer);
+}