review request (S): 7087453: PhaseChaitin::yank_if_dead() should handle MachTemp inputs

[Roland Westrelin]

http://cr.openjdk.java.net/~roland/7087453/webrev.00/

When PhaseChaitin::yank_if_dead() hits a node with MachTemp inputs it crashes the VM with assertion:
assert(old->req() <= 2, "can't handle more inputs");
It should be able to handle MachTemps as a special case by yanking them as well.

Roland.