update to new kexec, and fix building with 17.06.1
update to new kexec, and fix building with 17.06.1

Signed-off-by: Sven Dowideit <dd860110a62b19214c4ee03aec0abffecb4e86b8@y260.home.org.au>

juliengk/os,ibuildthecloud/os,rancherio/os,gizmotronic/os,SvenDowideit/os,gizmotronic/os,rancher/os,ibuildthecloud/os,SvenDowideit/os,juliengk/os,rancherio/os,rancherio/os,rancher/os