Apply even more fixups

- Finish cleaning up the stdio unlocked APIs
- Make __cxa_finalize() properly thread safe
- Don't log locks if threads aren't being used
- Add some more mutex guards to places using _mmi
- Specific lock names now appear in the --ftrace logs
- Fix mkdeps.com generating invalid Makefiles sometimes
- Simplify and fix bugs in the test runner infrastructure
- Fix issue where sometimes some functions wouldn't be logged

libc/stdio/putchar.c

@@ -22,7 +22,8 @@
  * Writes byte to stdout.
  *
  * @return c (as unsigned char) if written or -1 w/ errno
+ * @threadsafe
  */
-int putchar_unlocked(int c) {
-  return fputc_unlocked(c, stdout);
+int putchar(int c) {
+  return fputc(c, stdout);
 }