Remove old thread_local.h

This was to work around a clang 9.0.0 bug.  We are on clang 13.  Make
things simpler by removing it.

Change-Id: I4bad16270795bb82b8c498146a4bf7388565a1c7
Signed-off-by: Austin Schuh <austin.linux@gmail.com>
diff --git a/aos/ipc_lib/aos_sync.cc b/aos/ipc_lib/aos_sync.cc
index b8bd7a3..6bf5d8c 100644
--- a/aos/ipc_lib/aos_sync.cc
+++ b/aos/ipc_lib/aos_sync.cc
@@ -33,7 +33,6 @@
 #include "glog/logging.h"
 
 #include "aos/macros.h"
-#include "aos/thread_local.h"
 #include "aos/util/compiler_memory_barrier.h"
 
 using ::aos::linux_code::ipc_lib::RunShmObservers;
@@ -447,7 +446,7 @@
 
 // Starts off at 0 in each new thread (because that's what it gets initialized
 // to in most of them or it gets to reset to 0 after a fork by atfork_child()).
-AOS_THREAD_LOCAL pid_t my_tid = 0;
+thread_local pid_t my_tid = 0;
 
 // Gets called before the fork(2) wrapper function returns in the child.
 void atfork_child() {
@@ -506,7 +505,7 @@
 static_assert(sizeof(aos_robust_list_head) == sizeof(robust_list_head),
               "Our aos_robust_list_head doesn't match the kernel's");
 
-AOS_THREAD_LOCAL aos_robust_list_head robust_head;
+thread_local aos_robust_list_head robust_head;
 
 // Extra offset between mutex values and where we point to for their robust list
 // entries (from SetRobustListOffset).