[mlir][SIdeEffectInterface][NFC] Move several InterfaceMethods to the...

[mlir][SIdeEffectInterface][NFC] Move several InterfaceMethods to the extraClassDeclarations instead

All InterfaceMethods will have a corresponding entry in the interface model, and by extension have an implementation generated for every operation type. This can result in large binary size increases when a large amount of operations use an interface, such as the side effect interface.

Differential Revision: https://reviews.llvm.org/D90084