Hi Nota and welcome to GoY. I think you will have great difficulty in growing raspberries in five inches of soil, also as they are canes and have a tendency to suckering you are likely to get damage to the wall. Raspberries really need to be grown in a good deep bed of soil with access to both sides to enable you to pick the berries and to prune out the canes that have already fruited in autumn.

The edge of footings for a double brick (9 ins wall) probably won't extend too far from the wall. The rule of thumb when building footings for a wall is that the footings should be twice as wide as the wall, which should be about 18 ins, so the edge of the footings will only be about 4 - 5 ins away from the wall, dig a test hole and check. If this is the case then you could plant them about a foot away from the wall.

If the wall is a boundary wall this could cause problems for you with your neighbour, but the footings might even act as a barrier and stop the roots from getting to the other side of the wall. However, depending on how high the wall is, the footings might not be that deep and the roots might get under it.