Add some missing includes that GCC 12 wants to see

lib/libdvbsub/dvbsubtitle.cpp

@@ -21,6 +21,7 @@ extern "C" {
 #include <libavformat/avformat.h>
 #include <libavcodec/avcodec.h>
 #include <libavutil/avutil.h>
+#include <pthread.h>
 }
 #include <driver/framebuffer.h>
 #include "Debug.hpp"

lib/libtuxtxt/tuxtxt.h

@@ -29,6 +29,7 @@
 #include <sys/types.h>
 #include <sys/time.h>
 #include <ctype.h>
+#include <pthread.h>
 
 #include <linux/fb.h>
 

lib/timerdclient/timerdclient.h

@@ -28,6 +28,7 @@
 #define __timerdclient__
 
 #include <string>
+#include <ctime>
 #include <cstring>
 
 #include <connection/basicclient.h>