[amd64] udeb: kernel-image: Include SPI drivers

As pointed out in Debian bug #1110007 on a 2017 MacBook Pro (MacBookPro14,1) during installation the Trackpad/keyboard is unusable.

Cyril Brulebois provided a netinst image incuding the required spi drivers, confirmed by Osama Albahrani to make things work.

Link: https://bugs.debian.org/1110007

/cc @kibi