Verify kill flags conservatively.
Verify kill flags conservatively.

Allow a live range to end with a kill flag, but don't allow a kill flag that
doesn't end the live range.

This makes the machine code verifier more useful during register allocation when
kill flag computation is deferred.

git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@124838 91177308-0d34-0410-b5e6-96231b3b80d8

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