pico: close open files when resetting the loader

Now daftboy works more than twice

32blit-pico/main.cpp

diff --git a/32blit-pico/main.cpp b/32blit-pico/main.cpp
index defd91f..0cd6606 100644
--- a/32blit-pico/main.cpp
+++ b/32blit-pico/main.cpp
@@ -215,6 +215,8 @@
 static int64_t home_hold_callback(alarm_id_t id, void *user_data) {
   home_hold_alarm_id = 0;
 
+  close_open_files();
+
   launch_pre_init();
   ::init(); // re-initialising the loader is effectively a reset
 

32blit-pico/usb.cpp

diff --git a/32blit-pico/usb.cpp b/32blit-pico/usb.cpp
index d823374..53d8238 100644
--- a/32blit-pico/usb.cpp
+++ b/32blit-pico/usb.cpp
@@ -10,6 +10,8 @@
 #include "multiplayer.hpp"
 #include "overlay.hpp"
 
+#include "fatfs_blit_api.hpp"
+
 #include "engine/engine.hpp"
 #include "executable.hpp"
 
@@ -173,6 +175,7 @@
             usb_cdc_flush_write();
 
             // reinit loader
+            close_open_files();
             ::init();
 
             return Status::Done;