SimplifyCFG: fix an infinite jump-threading loop.
SimplifyCFG: fix an infinite jump-threading loop.

The JumpThreadingCost map in Simplify CFG is used to prevent infinite jump threading loops.
There was a missing update of the cost for blocks which are cloned:
Jump threading loops were prevented for infinitely cloning the original block, but not for re-cloning the cloned block.

A test case is already added in 8948f7565a2800e0378c2925085bf0a723089973

rdar://73357726, [SR-14068]

parkera/swift,gregomni/swift,xwu/swift,xwu/swift,apple/swift,gregomni/swift,parkera/swift,xwu/swift,atrick/swift,parkera/swift,ahoppen/swift,xwu/swift,benlangmuir/swift,roambotics/swift,rudkx/swift,hooman/swift,tkremenek/swift,gregomni/swift,glessard/swift,JGiola/swift,atrick/swift,rudkx/swift,xwu/swift,tkremenek/swift,roambotics/swift,rudkx/swift,apple/swift,glessard/swift,rudkx/swift,parkera/swift,apple/swift,JGiola/swift,roambotics/swift,atrick/swift,glessard/swift,rudkx/swift,tkremenek/swift,hooman/swift,ahoppen/swift,hooman/swift,ahoppen/swift,ahoppen/swift,atrick/swift,glessard/swift,apple/swift,JGiola/swift,parkera/swift,benlangmuir/swift,hooman/swift,ahoppen/swift,tkremenek/swift,JGiola/swift,gregomni/swift,gregomni/swift,xwu/swift,tkremenek/swift,apple/swift,benlangmuir/swift,benlangmuir/swift,parkera/swift,roambotics/swift,glessard/swift,hooman/swift,benlangmuir/swift,JGiola/swift,parkera/swift,gregomni/swift,benlangmuir/swift,JGiola/swift,roambotics/swift,atrick/swift,atrick/swift,roambotics/swift,hooman/swift,glessard/swift,hooman/swift,apple/swift,tkremenek/swift,xwu/swift,parkera/swift,tkremenek/swift,rudkx/swift,ahoppen/swift