fix: fix modrm parsing

Previously the wrong register was read in, now
the byte is deconstructed correctly

src/instructions.rs

@@ -61,6 +61,7 @@ impl fmt::Display for Opcode {
 }
 
 /// Registers of a 8086 processor
+/// -x are 16bit, -l are 8bit
 #[derive(Debug, Clone)]
 #[allow(dead_code)]
 pub enum Register {