Stencils with multiple ranges should sometimes get access-pattern specs

[dorchard]

e.g. p(:,0) = sum(q(:,1,:))
Investigate further what the correct behaviour is here. This currently gets the specification
stencil readOnce, (reflexive(dim=1))*(reflexive(dim=3)) :: q
But I believe this is an example which is not a true stencil. Instead this should merely be an access pattern:
access readOnce, (reflexive(dim=1))*(reflexive(dim=3)) :: q

[dorchard]

Reconsider in light of 8b5c622

[dorchard]

Note that the equivalent code here would be:

do i = 1, 2
  s = 0
  do j = 1, 2
    do k = 1, 3
      s = s + q(j,1,k)
    end do
  end do
  p(i,0) = s
end do

Which currently does not get the access stencil inferred which seems like a bug.