MFC r305739-r305740

r305739:
Use "generic" ALLWINNER_UP kernel config for Cubieboard release.

Reviewed by: gjb
MFC after: 2 week

r305740:
Remove CUBIEBOARD kernel config file.
Every Allwinner board should either use ALLWINNER (SMP) or ALLWINER_UP kernel
config files.

MFC after: 2 week