shader/shader_ir: Amend constructor initializer ordering for AbufNode

Orders the class members in the same order that they would actually be
initialized in. Gets rid of two compiler warnings.

src/video_core/shader/shader_ir.h

@@ -415,11 +415,11 @@ class AbufNode final {
 public:
     explicit constexpr AbufNode(Tegra::Shader::Attribute::Index index, u32 element,
                                 const Tegra::Shader::IpaMode& input_mode, Node buffer = {})
-        : input_mode{input_mode}, index{index}, element{element}, buffer{buffer} {}
+        : input_mode{input_mode}, buffer{buffer}, index{index}, element{element} {}
 
     explicit constexpr AbufNode(Tegra::Shader::Attribute::Index index, u32 element,
                                 Node buffer = {})
-        : input_mode{}, index{index}, element{element}, buffer{buffer} {}
+        : input_mode{}, buffer{buffer}, index{index}, element{element} {}
 
     Tegra::Shader::IpaMode GetInputMode() const {
         return input_mode;