oldland: fix dst max for 13-bit relocations.

Signed-off-by: Jamie Iles <jamie@jamieiles.com>
oldland: explicitly set PC relative relocation types.

Signed-off-by: Jamie Iles <jamie@jamieiles.com>
oldland: update opcode definitions from upstream.

Signed-off-by: Jamie Iles <jamie@jamieiles.com>