Bump Iris + get rid of iAlways.

opam

theories/lang/lib/arc.v

theories/lang/lib/lock.v

theories/lang/lifting.v

theories/lifetime/frac_borrow.v

theories/lifetime/lifetime.v

theories/lifetime/model/borrow_sep.v

theories/lifetime/model/creation.v

theories/lifetime/model/primitive.v

theories/typing/function.v

theories/typing/lib/arc.v

theories/typing/lib/cell.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/refmut.v