[NewPM][Hexagon] Fix HexagonVectorLoopCarriedReusePass position in pipeline

In https://reviews.llvm.org/D88138 this was incorrectly added with
registerOptimizerLastEPCallback(), when it should be
registerLoopOptimizerEndEPCallback(), matching the legacy PM's
EP_LoopOptimizerEnd.

Reviewed By: rnk

Differential Revision: https://reviews.llvm.org/D93929