[D11] Make sure all the hairset mappings are complete, i.e. don't rely on a certain model being set on the prefab for the default male. The reason is we need the hairsets to completely specify these meshes used in conjunction with the MorphCache if we're going to bake out the morph poses at build time. Second commit to follow which actually implements this optimization, this changest shouldn't actually change anything other than make the current behaviour explicit.