the reason for checking `EBADF|EINVAL` specifically is unknown. but it's
clearly not working as intended since it can cause issues like #11795.
instead of checking for "bad errors" check for known "good errors" where
we might not want to break out. this includes:
* EINTR: which can happen if read() is interrupted by some signal.
* EAGAIN: which happens if a non-blocking fd would block. `tty_in` is
_not_ non-blocking, so EAGAIN should never occur here. but it's added
just in case that changes in the future.
Fixes: https://github.com/mpv-player/mpv/issues/11795
Closes: https://github.com/mpv-player/mpv/pull/11805