[clang][dataflow] Replace `transfer(const Stmt *, ...)` with `transfer(const...

[clang][dataflow] Replace `transfer(const Stmt *, ...)` with `transfer(const CFGElement *, ...)` in `Analysis/FlowSensitive/Models/UncheckedOptionalAccessModel`.

Reviewed By: gribozavr2, sgatev

Differential Revision: https://reviews.llvm.org/D133930