[oe] Move IMAGE_BOOT stuff into distro's?

[Leon Woestenberg]

Why do we hardcode names of default packages in the "image.bbclass"?

Now every image recipe that doesn't want these has to know the
variables it has to override.

Shouldn't this be distro material instead?

#
# udev, devfsd, busybox-mdev (from busybox) or none
#
IMAGE_DEV_MANAGER ?= "${@base_contains("MACHINE_FEATURES", "kernel26",
 "udev","",d)} "
#
# sysvinit, upstart
#
IMAGE_INIT_MANAGER ?= "sysvinit sysvinit-pidof"
IMAGE_INITSCRIPTS ?= "initscripts"
#
# tinylogin, getty
#
IMAGE_LOGIN_MANAGER ?= "tinylogin"

IMAGE_KEEPROOTFS ?= ""
IMAGE_KEEPROOTFS[doc] = "Set to non-empty to keep ${IMAGE_ROOTFS}
around after image creation."

IMAGE_BOOT ?= "${IMAGE_INITSCRIPTS} \
${IMAGE_DEV_MANAGER} \
${IMAGE_INIT_MANAGER} \
${IMAGE_LOGIN_MANAGER} "

Regards,
-- 
Leon