Revert "[GlobalISel] Refactor the artifact combiner a bit by using MIPatternMatch"

This reverts r346166 as it breaks
test-suite-verify-machineinstrs-aarch64-globalisel-O0-g.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346175 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed