InstCombine: Combine (add (and %a, %b) (or %a, %b)) to (add %a, %b)

What follows bellow is a correctness proof of the transform using CVC3.

$ < t.cvc
A, B : BITVECTOR(32);

QUERY BVPLUS(32, A & B, A | B) = BVPLUS(32, A, B);

$ cvc3 < t.cvc
Valid.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215400 91177308-0d34-0410-b5e6-96231b3b80d8