LibWasm: Parse the "extend" set of instructions

Author: https://github.com/alimpfard
Commit: 02b3238c41
Pull-request: https://github.com/SerenityOS/serenity/pull/7670

Userland/Libraries/LibWasm/Opcode.h

@@ -187,6 +187,11 @@ static constexpr OpCode unreachable = 0x00,
                         i64_reinterpret_f64 = 0xbd,
                         f32_reinterpret_i32 = 0xbe,
                         f64_reinterpret_i64 = 0xbf,
+                        i32_extend8_s = 0xc0,
+                        i32_extend16_s = 0xc1,
+                        i64_extend8_s = 0xc2,
+                        i64_extend16_s = 0xc3,
+                        i64_extend32_s = 0xc4,
                         ref_null = 0xd0,
                         ref_is_null = 0xd1,
                         ref_func = 0xd2;