FILO.FS.VFS: Close currently open file before opening new one

This is what FILO's current behavior implies (->close_func doesn't
get called).
1 file changed
tree: cf635292770b44f932160d71f0068c18de57bfe5
  1. src/
  2. .gitignore
  3. default.adc
  4. default.gpr
  5. default.nix