tty: Mark tty_del_file and __tty_hangup static

Nothing outside of drivers/tty/tty_io.c references these functions, so
mark them static.

Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1 file changed