remove non-standard enum fwd decl

examples/plugin/cpu-plugin.cpp

@@ -1,6 +1,5 @@
 #include "model.hpp"
 
-#include <ggml.h>
 #include <ggml-backend.h>
 
 #include <vector>

examples/plugin/model.cpp

@@ -1,6 +1,5 @@
 #include "model.hpp"
 
-#include <ggml.h>
 #include <ggml-alloc.h>
 #include <ggml-backend.h>
 

examples/plugin/model.hpp

@@ -1,10 +1,8 @@
 #pragma once
+#include <ggml.h>
 #include <cstdint>
 
-struct ggml_tensor;
 typedef struct ggml_backend* ggml_backend_t;
-struct ggml_context;
-enum ggml_type;
 struct ggml_backend_buffer;
 struct ggml_allocr;