libtriple: convert tripledragon remote to uinput

Instead of patching neutrino to read the Tripledragon remote, use a
converter thread in libtriple to convert the TD remote to a real input
device via uinput.

libtriple/lt_dfbinput.h

@@ -0,0 +1,7 @@
+/* functions from lt_dfbinput.c */
+
+#ifndef __LT_DFB_INPUT_H_
+#define __LT_DFB_INPUT_H_
+void start_input_thread(IDirectFB *dfb);
+void stop_input_thread(void);
+#endif