convert adc/sbb to a multipattern. Because the adde/sube nodes

convert adc/sbb to a multipattern.  Because the adde/sube nodes
are not defined as returning EFLAGS (like add_flag and friends),
the entire multipattern and several of the subclasses need to be
cloned.

This could be handled through better instantiation support in tblgen,
but it isn't meta enough.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@115964 91177308-0d34-0410-b5e6-96231b3b80d8