pti: ENXIO error case memory leak PTI fix.

This patch fixes a memory leak that can occur in the error case
ENXIO is returned in the pti_tty_install() routine.

Signed-off-by: J Freyensee <james_p_freyensee@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>