ttytype(): Fix race

ttytype(): Fix race

The intention of the code is just to not report an error message when
'typefile' doesn't exist.  If we call access(2) and then fopen(2),
there's a race.  It's not a huge problem, and the worst thing that can
happen is reporting an error when the file has been removed after
access(2).  It's not a problem, but we can fix the race and at the same
time clarify the intention of not warning about ENOENT and also remove
one syscall.  Seems like a win-win.

Suggested-by: Christian Göttsche <cgzones@googlemail.com>
Signed-off-by: Alejandro Colomar <alx@kernel.org>