Fixes the following W=1 kernel build warning(s):
 drivers/tty/pty.c:710: warning: Function parameter or member 'file' not described in 'ptm_unix98_lookup'
 drivers/tty/pty.c:726: warning: Function parameter or member 'file' not described in 'pts_unix98_lookup'
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: "C. Scott Ananian" <cananian@alumni.princeton.edu>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20201104193549.4026187-17-lee.jones@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
 /**
  *     ptm_unix98_lookup       -       find a pty master
  *     @driver: ptm driver
+ *     @file: unused
  *     @idx: tty index
  *
  *     Look up a pty master device. Called under the tty_mutex for now.
 /**
  *     pts_unix98_lookup       -       find a pty slave
  *     @driver: pts driver
+ *     @file: file pointer to tty
  *     @idx: tty index
  *
  *     Look up a pty master device. Called under the tty_mutex for now.