Blender Git Loki

[#18159] Path -> toggle cyclic -> toggle cyclic again == path corrupted
was not recalculating the knots when the cyclic flag was disabled so the endpoint flag was being ignored until recalculating (extrude for eg).

Also removed unneeded re-allocation of curve knots which are always reallocated by makeknots.

Fixed another bug with which recalculating knots with the Python surface api. (mixed up u/v args to makeknots(..) )