[InstCombine] fold more constant divisor to select-of-constants divisor

By adding a parameter to function FoldOpIntoSelect， we can fold more Ops to Select.
For this example, we tend to fold the division instruction,
so we no longer care whether SelectInst is one use.

This patch slove TODO left in InstCombine/div.ll.

Reviewed By: RKSimon

Differential Revision: https://reviews.llvm.org/D122967