renderer_opengl/utils: Use a std::string_view with LabelGLObject()

Uses a std::string_view instead of a std::string, given the pointed to
string isn't modified and is only used in a formatting operation.

This is nice because a few usages directly supply a string literal to
the function, allowing these usages to otherwise not heap allocate,
unlike the std::string overloads.

While we're at it, we can combine the address formatting into a single
formatting call.

src/video_core/renderer_opengl/utils.h

@@ -4,7 +4,7 @@
 
 #pragma once
 
-#include <string>
+#include <string_view>
 #include <vector>
 #include <glad/glad.h>
 #include "common/common_types.h"
@@ -30,6 +30,6 @@ private:
     std::vector<GLsizeiptr> sizes;
 };
 
-void LabelGLObject(GLenum identifier, GLuint handle, VAddr addr, std::string extra_info = "");
+void LabelGLObject(GLenum identifier, GLuint handle, VAddr addr, std::string_view extra_info = {});
 
 } // namespace OpenGL