[SimplifyCFG] HoistThenElseCodeToIf(): don't hoist if either block has it's address taken
This problem is exposed by D104598, after it tail-merges ret in
@test_inline_constraint_S_label, the verifier would start complaining
invalid operand for inline asm constraint 'S'.
Essentially, taking address of a block is mismodelled in IR.
It should probably be an explicit instruction, a first one in block,
that isn't identical to any other instruction of the same type,
so that it can't be hoisted.