pan/midgard: Tableize load/store ops

pan/midgard: Tableize load/store ops

This will allow us to encode properties about the load/store ops like we
do for ALU ops. We include now properties about whether we have a store,
and if there are special cases on the load/store op. We also tag each
instruction by its natural size... this is probably not totally right,
but it's a start.

Signed-off-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>