Blender Git Loki

Armature: remove remains of the object-level deformation data cache.

Now that B-Bone shape data is kept in bPoseChannel_Runtime, the
armature level cache only holds one quaternion value per bone.
It can also be moved to runtime, and the structure removed.

This has an additional effect that, as far as I can tell, now
the Armature modifier can run as soon as all of the bones it
actually needs are done, thus making T59848 a purely depsgraph
level problem.