shader: Simplify code in opcodes.h to fix Intellisense

Avoid using std::array to fix Intellisense not properly compiling this
code and disabling itself on all files that include it.

While we are at it, change the code to use u8 instead of size_t for the
number of instructions in an opcode.

src/shader_recompiler/frontend/ir/opcodes.h

@@ -4,8 +4,8 @@
 
 #pragma once
 
-#include <array>
 #include <algorithm>
+#include <array>
 #include <string_view>
 
 #include <fmt/format.h>
@@ -21,7 +21,6 @@ enum class Opcode {
 };
 
 namespace Detail {
-
 struct OpcodeMeta {
     std::string_view name;
     Type type;
@@ -57,9 +56,9 @@ constexpr Type F64x2{Type::F64x2};
 constexpr Type F64x3{Type::F64x3};
 constexpr Type F64x4{Type::F64x4};
 
-constexpr std::array META_TABLE{
+constexpr OpcodeMeta META_TABLE[]{
 #define OPCODE(name_token, type_token, ...)                                                        \
-    OpcodeMeta{                                                                                    \
+    {                                                                                              \
         .name{#name_token},                                                                        \
         .type = type_token,                                                                        \
         .arg_types{__VA_ARGS__},                                                                   \
@@ -67,14 +66,13 @@ constexpr std::array META_TABLE{
 #include "opcodes.inc"
 #undef OPCODE
 };
-
 constexpr size_t CalculateNumArgsOf(Opcode op) {
     const auto& arg_types{META_TABLE[static_cast<size_t>(op)].arg_types};
     return std::distance(arg_types.begin(), std::ranges::find(arg_types, Type::Void));
 }
 
-constexpr std::array NUM_ARGS{
-#define OPCODE(name_token, type_token, ...) CalculateNumArgsOf(Opcode::name_token),
+constexpr u8 NUM_ARGS[]{
+#define OPCODE(name_token, type_token, ...) static_cast<u8>(CalculateNumArgsOf(Opcode::name_token)),
 #include "opcodes.inc"
 #undef OPCODE
 };
@@ -87,7 +85,7 @@ constexpr std::array NUM_ARGS{
 
 /// Get the number of arguments an opcode accepts
 [[nodiscard]] inline size_t NumArgsOf(Opcode op) noexcept {
-    return Detail::NUM_ARGS[static_cast<size_t>(op)];
+    return static_cast<size_t>(Detail::NUM_ARGS[static_cast<size_t>(op)]);
 }
 
 /// Get the required type of an argument of an opcode