tty_exist(): Simplify, no need to call access() and then open()
tty_exist(): Simplify, no need to call access() and then open()

Found by Coverity Scan, classified as security issue but was just
unnecessary overhead.

Signed-off-by: Joachim Nilsson <583c295fd7602c168ad814279bbc3894ba65f5d6@gmail.com>

troglobit/finit,troglobit/finit