add a TODO to the linux logging implementation

Change-Id: Ibdf30fd287cc63f78709f1b609de7b5c36e0f616
diff --git a/aos/linux_code/logging/linux_interface.cc b/aos/linux_code/logging/linux_interface.cc
index f3ea9e0..0945ddd 100644
--- a/aos/linux_code/logging/linux_interface.cc
+++ b/aos/linux_code/logging/linux_interface.cc
@@ -10,6 +10,8 @@
 namespace internal {
 namespace {
 
+// TODO(brians): Differentiate between threads in the same process.
+
 ::std::string GetMyName() {
   // The maximum number of characters that can make up a thread name.
   // The docs are unclear if it can be 16 characters with no '\0', so we'll be