kernel.bbclass, module.bbclass: Make update-modules optional
The update-modules mechanism is something of a historical relic and it isn't
entirely clear that it has a great deal of value nowadays. Also, it causes a
problem when building a read-only rootfs since update-modules itself refuses
to configure offline.
Allow DISTROs to circumvent this whole thing by declaring (via DISTRO_FEATURES)
that they don't wish to use update-modules. This is backfilled for existing
distributions and will have to be marked as CONSIDERED by those who actually
don't want it.
Signed-off-by: Phil Blundell <pb@pbcl.net> Signed-off-by: Saul Wold <sgw@linux.intel.com>
