access to P9 on buttons manipulation

[mister-grumbler]

severity is low
description:
the menu switches into parameter selection mode with parameter index = 9 which is forbidden for direct access and should not be available for selection.
use case:
at root menu press shortly button "set".
-> value for fermentation timer will be shown (blinking).
immediately press and hold "set" button for long time (about 5-10 seconds).
-> P9 parameter index will be shown.