virCPUData, virCPUx86Feature, and virCPUx86Model all contained a pointer
to virCPUx86Data, which was not very nice since the real CPUID data were
accessible by yet another pointer from virCPUx86Data. Moreover, using
virCPUx86Data directly will make static definitions of internal CPU
features a bit easier.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>