Add pinning to model of types

theories/typing/borrow.v

theories/typing/fixpoint.v

theories/typing/function.v

theories/typing/lib/arc.v

theories/typing/lib/brandedvec.v

theories/typing/lib/cell.v

theories/typing/lib/fake_shared.v

theories/typing/lib/ghostcell.v

theories/typing/lib/join.v

theories/typing/lib/mutex/mutex.v

theories/typing/lib/mutex/mutexguard.v

theories/typing/lib/rc/rc.v

theories/typing/lib/rc/weak.v

theories/typing/lib/refcell/ref.v

theories/typing/lib/refcell/ref_code.v

theories/typing/lib/refcell/refcell.v

theories/typing/lib/refcell/refcell_code.v

theories/typing/lib/refcell/refmut.v

theories/typing/lib/rwlock/rwlock.v

theories/typing/lib/rwlock/rwlock_code.v