For each instruction itinerary class, specify the number of micro-ops each

For each instruction itinerary class, specify the number of micro-ops each
instruction in the class would be decoded to. Or zero if the number of
uOPs must be determined dynamically.

This will be used to determine the cost-effectiveness of predicating a
micro-coded instruction.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@113513 91177308-0d34-0410-b5e6-96231b3b80d8