linux-headers: Update to kernel mainline commit b357bf602

Update our kernel headers to mainline commit
b357bf6023a948cf6a9472f07a1b0caac0e4f8e8
("Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm")

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Message-id: 1529072910-16156-2-git-send-email-eric.auger@redhat.com
[PMM:  clarified commit message]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>