LibGPU: Add inputs and outputs to GPU shader IR

Author: https://github.com/sunverwerth
Commit: c88bc74afd
Pull-request: https://github.com/SerenityOS/serenity/pull/16225
Reviewed-by: https://github.com/ADKaster ✅
Reviewed-by: https://github.com/gmta ✅
Reviewed-by: https://github.com/supercomputer7

Userland/Libraries/LibGPU/IR.h

@@ -72,6 +72,8 @@ struct Temporary final {
 struct Shader final {
     Vector<Constant> constants;
     Vector<Uniform> uniforms;
+    Vector<Input> inputs;
+    Vector<Output> outputs;
     Vector<Temporary> temporaries;
     Vector<Instruction> instructions;
 };