config-gui.sh: Integrate PureBoot Basic changes

config-gui-basic.sh is just config-gui.sh with the options relating to verified boot removed. Re-integrate by omitting the relevant options from the whiptail menu in basic mode.

ash lacks arrays, so write a script that invokes whiptail in order to build the menu items dynamically. The only alternative is building the parameters in a single variable that the shell would word-split, but the quoting for this would be even worse since many of the parameters contain spaces.

Signed-off-by: Jonathon Hall jonathon.hall@puri.sm