swift234

Revert "Change the SILLocations for enum element dispatches to make the line table"

This reverts commit r22739 because it broke an unreachable code test
and is blocking the bots.

The problem can be reproduced with:
  swift -frontend  -disable-objc-attr-requires-foundation-module -emit-sil test/SILPasses/unreachable_code.swift -o /dev/null -verify

Swift SVN r22750