Similar to previous patches, let's improve the insert() descent loop to
avoid discovering mandatory data too late. The change here is even
simpler than previous ones, a prefetch was installed and troot is
calculated before last instruction in a speculative way. This was enough
to gain +50% insertion rate on random data.
This is ebtree commit e893f8cc4d44b10f406b9d1d78bd4a9bd9183ccf.
3dda813d54