Avoid dbg.value use-before-def in a few tests (NFC)

This is preparation for landing a use-before-def verifier for debug
intrinsics (D46100).

As a drive-by, remove `tail` from debug intrinsic calls because it
doesn't mean anything in that context.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@340366 91177308-0d34-0410-b5e6-96231b3b80d8
4 files changed