Comment # 6 on bug 1226122 from Thorsten Kukuk

(In reply to Felix Miata from comment #5)
> The installer needs to be adapted to receive input related to "not managed"
> and what the results of kernel and dracut installation should include, such
> as radio buttons or checkboxes for /boot/, /boot/efi/, neither, discrete
> filesystem, etc. handled through /etc/alternatives or /etc/sysconfig.

The installer does not copy the kernel or initrd into /boot, this are the
bootloader scripts. Letting the installer do this wouldn't make any sense
because you want to update this files with the next update, too. 
And if you have no bootloader, nothing is copying the kernel, because nothing
which could do it get's installed. See my previous comment, the kernel must be
in the location where the selected bootloader needs it, not in a random place.

I'm afraid you need to create your own scripts for your bootloader, as that is
not shipped with openSUSE.