Move over to ABSL logging and flags.

Removes gperftools too since that wants gflags.

Here come the fireworks.

Change-Id: I79cb7bcf60f1047fbfa28bfffc21a0fd692e4b1c
Signed-off-by: Austin Schuh <austin.linux@gmail.com>
diff --git a/y2023/vision/game_pieces_main.cc b/y2023/vision/game_pieces_main.cc
index b4ceff5..ff3ec7c 100644
--- a/y2023/vision/game_pieces_main.cc
+++ b/y2023/vision/game_pieces_main.cc
@@ -1,15 +1,18 @@
+#include "absl/flags/flag.h"
+
 #include "aos/events/shm_event_loop.h"
 #include "aos/init.h"
 #include "y2023/vision/game_pieces.h"
 
-DEFINE_string(config, "aos_config.json", "Path to the config file to use.");
+ABSL_FLAG(std::string, config, "aos_config.json",
+          "Path to the config file to use.");
 
 namespace y2023::vision {
 namespace {
 
 void GamePiecesDetectorMain() {
   aos::FlatbufferDetachedBuffer<aos::Configuration> config =
-      aos::configuration::ReadConfig(FLAGS_config);
+      aos::configuration::ReadConfig(absl::GetFlag(FLAGS_config));
   aos::ShmEventLoop event_loop(&config.message());
   GamePiecesDetector game_pieces_detector(&event_loop);
   event_loop.Run();