stage2 x86_64: refactor codegen to use inst encoder

There are parts of it that I didn't modify because the byte
representation was important (e.g. we need to know what the exact
byte position where we store the address into the offset table is)
36df1526dagracefu committed on 4/16/2021, 7:21:17 AMparente1959cc
1 file changedLine totals unavailable