[interpreter] Add support for scalable operands.

test/cctest/interpreter/bytecode_expectations/LookupSlotInEval.golden

 #
 # Autogenerated by generate-bytecode-expectations.
 #
 
 ---
 pool type: string
 execute: yes
 wrap: no
 test function name: f
 
@@ skipping 27 matching lines @@
   function f1() {
     eval(\"function t() { x = 10; }; f = t; f();\");
   }
   f1();
 "
 frame size: 0
 parameter count: 1
 bytecode array length: 7
 bytecodes: [
   B(StackCheck),
-  B(LdaSmi8), U8(10),
+  B(LdaSmi), U8(10),
   B(StaLookupSlotSloppy), U8(0),
   B(LdaUndefined),
   B(Return),
 ]
 constant pool: [
   "x",
 ]
 handlers: [
 ]
 
 ---
 snippet: "
   var f;
   var x = 1;
   function f1() {
     eval(\"function t() { 'use strict'; x = 10; }; f = t; f();\");
   }
   f1();
 "
 frame size: 0
 parameter count: 1
 bytecode array length: 7
 bytecodes: [
   B(StackCheck),
-  B(LdaSmi8), U8(10),
+  B(LdaSmi), U8(10),
   B(StaLookupSlotStrict), U8(0),
   B(LdaUndefined),
   B(Return),
 ]
 constant pool: [
   "x",
 ]
 handlers: [
 ]
 
@@ skipping 14 matching lines @@
   B(LdaLookupSlotInsideTypeof), U8(0),
   B(TypeOf),
   B(Return),
 ]
 constant pool: [
   "x",
 ]
 handlers: [
 ]