Print a warning if two devices are sharing the same interrupt

Print a warning if two devices are sharing the same interrupt
Update profile-top to print 2 or 4 graphs depending on a command line
option

dev/pciconfigall.cc:
dev/pciconfigall.hh:
dev/pcidev.hh:
    Print a warning if two devices are sharing the same interrupt

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extra : convert_revision : 0ef99cac92fbf2916ab8e5b1125d520eb4b5ac7d