The kernel with USERCONFIG_BOOT and VISUAL_USERCONFIG option presents
the user the kernel configuration menu upon boot.
The user can navigate the menu with cursor keys. I think it would be
nice if the user can navigate and select a menu item with regular keys
as well, so that the user who is using a serial console which is not
so capable of esc sequences still can choose a menu item.
With the following patch we can select an item by typing an item
number, 1, 2, or 3, or mnemonic `s' to skip UserConfig, 'v' to enter
the visual mode, and `c' to start the CLI mode. `p', `u', `n', and `d'
will move cursor up and down.
Submitted by: yokota
fca71c8053