For ports with MICROPY_VFS and MICROPY_PY_IO enabled their configuration
can now be simplified to use the defaults for mp_import_stat and
mp_builtin_open.
This commit makes no functional change, except for the following minor
points:
- the built-in "open" is removed from the minimal port (it previously did
nothing)
- the duplicate built-in "input" is removed from the esp32 port
- qemu-arm now delegates to VFS import/open
Signed-off-by: Damien George <damien@micropython.org>
Takeo Takahashi