Now compiles under GCC 10 (GCC 10 now defaults to -fno-common)

source/fs.c

@@ -31,6 +31,10 @@
  
 #include <archive.h>
 #include <archive_entry.h>
+
+FS_Archive ArchiveSD;
+FS_Archive ArchiveHomeExt;
+FS_Archive ArchiveThemeExt;
  
 Result open_archives(void)
 {
@@ -203,4 +207,4 @@ void remake_file(FS_Path path, FS_Archive archive, u32 size)
     char *buf = calloc(size, 1);
     buf_to_file(size, path, archive, buf);
     free(buf);
-}
+}