gl_shader_cache: Remove unused program_code vector in GetShaderAddress()

Given std::vector is a type with a non-trivial destructor, this
variable cannot be optimized away by the compiler, even if unused.
Because of that, something that was intended to be fairly lightweight,
was actually allocating 32KB and deallocating it at the end of the
function.

src/video_core/renderer_opengl/gl_shader_cache.cpp

@@ -14,9 +14,8 @@ namespace OpenGL {
 /// Gets the address for the specified shader stage program
 static Tegra::GPUVAddr GetShaderAddress(Maxwell::ShaderProgram program) {
     auto& gpu = Core::System::GetInstance().GPU().Maxwell3D();
-
-    GLShader::ProgramCode program_code(GLShader::MAX_PROGRAM_CODE_LENGTH);
     auto& shader_config = gpu.regs.shader_config[static_cast<size_t>(program)];
+
     return gpu.regs.code_address.CodeAddress() + shader_config.offset;
 }