cubieboard2: added network kernel module as essential dependency
cubieboard2: added network kernel module as essential dependency

Adding sunxi_emac network driver as recommended *essential* machine dependency, rather than recommended *extra* dependency, to make sure it is included, even if packagegroup-base is not included.

See also https://www.yoctoproject.org/docs/current/ref-manual/ref-manual.html#var-MACHINE_EXTRA_RDEPENDS

Also removed kernel26, as this is deprecated, see http://www.openembedded.org/wiki/Migrating_metadata_to_OE-Core

O-Computers/meta-sunxi,net147/meta-sunxi,twoerner/meta-sunxi,jlucius/meta-sunxi,rofehr/meta-sunxi,net147/meta-sunxi,rofehr/meta-sunxi,twoerner/meta-sunxi,rofehr/meta-sunxi,O-Computers/meta-sunxi,ebutera/meta-sunxi,soderstrom-rikard/meta-sunxi,soderstrom-rikard/meta-sunxi,jlucius/meta-sunxi,remahl/meta-sunxi,jlucius/meta-sunxi,linux-sunxi/meta-sunxi,O-Computers/meta-sunxi,linux-sunxi/meta-sunxi,geomatsi/meta-sunxi,linux-sunxi/meta-sunxi,geomatsi/meta-sunxi,ebutera/meta-sunxi