If an IR's BasicBlock jumps to itself, the Cogit code generated from it will be broken

[doste]

When dealing with an IR that has a self loop, the IR->Cogit translation is broken.
If a BasicBlock has a Jump to itself, the Cogit code generated will have an infinite loop.

A concrete example of this can be seen when generating the primitive primitiveLoopIncrementing.
Here we can see that the corresponding IR, after some the optimizations, will have a BasicBlock jumping to itself.

To check this we can do something like this:

        cfg := self generateBasicDruidIRFor: #primitiveLoopIncrementing.
	self optimize: cfg.
	1halt.

There if we inspect the CFG we can see the said block.
Then, we can check that gen_primitiveLoopIncrementing contains an infinite loop.