[ConstantHoisting] Add a TTI hook to prevent hoisting. (#69004)

Code generation can sometimes simplify expensive operations when
an operand is constant.  An example of this is divides on AArch64
where they can be rewritten using a cheaper sequence of multiplies
and subtracts.  Doing this is often better than hoisting expensive
constants which are likely to be hoisted by MachineLICM anyway.