* op-node: remove dependency on bindings

Removes the `op-node` dependency on the `op-bindings/bindings`
package. This moves `op-node` into a world where it relies
completely on bindings that it generates itself. A `make` recipe
could be useful for this in the future. This will enable us to say
that the `op-node` is compatible with particular releases of the
contracts.

This change was made by searching for
`"github.com/ethereum-optimism/optimism/op-bindings/bindings"`
in the codebase and replacing it.

There is still a dependency on `op-bindings/predeploys`, maybe
we want to keep that around or put them in a different package.

* bindings: fix build

* bindings: fixup