Excise DL_EXPORT from Include.

Thanks to Skip Montanaro and Kalle Svensson for the patches.
diff --git a/Include/objimpl.h b/Include/objimpl.h
index 730b032..2b35e67 100644
--- a/Include/objimpl.h
+++ b/Include/objimpl.h
@@ -94,20 +94,20 @@
    the object gets initialized via PyObject_{Init, InitVar} after obtaining
    the raw memory.
 */
-extern DL_IMPORT(void *) PyObject_Malloc(size_t);
-extern DL_IMPORT(void *) PyObject_Realloc(void *, size_t);
-extern DL_IMPORT(void) PyObject_Free(void *);
+PyAPI_FUNC(void *) PyObject_Malloc(size_t);
+PyAPI_FUNC(void *) PyObject_Realloc(void *, size_t);
+PyAPI_FUNC(void) PyObject_Free(void *);
 
 
 /* Macros */
 #ifdef WITH_PYMALLOC
 #ifdef PYMALLOC_DEBUG
-DL_IMPORT(void *) _PyObject_DebugMalloc(size_t nbytes);
-DL_IMPORT(void *) _PyObject_DebugRealloc(void *p, size_t nbytes);
-DL_IMPORT(void) _PyObject_DebugFree(void *p);
-DL_IMPORT(void) _PyObject_DebugDumpAddress(const void *p);
-DL_IMPORT(void) _PyObject_DebugCheckAddress(const void *p);
-DL_IMPORT(void) _PyObject_DebugMallocStats(void);
+PyAPI_FUNC(void *) _PyObject_DebugMalloc(size_t nbytes);
+PyAPI_FUNC(void *) _PyObject_DebugRealloc(void *p, size_t nbytes);
+PyAPI_FUNC(void) _PyObject_DebugFree(void *p);
+PyAPI_FUNC(void) _PyObject_DebugDumpAddress(const void *p);
+PyAPI_FUNC(void) _PyObject_DebugCheckAddress(const void *p);
+PyAPI_FUNC(void) _PyObject_DebugMallocStats(void);
 #define PyObject_MALLOC		_PyObject_DebugMalloc
 #define PyObject_Malloc		_PyObject_DebugMalloc
 #define PyObject_REALLOC	_PyObject_DebugRealloc
@@ -144,11 +144,11 @@
  */
 
 /* Functions */
-extern DL_IMPORT(PyObject *) PyObject_Init(PyObject *, PyTypeObject *);
-extern DL_IMPORT(PyVarObject *) PyObject_InitVar(PyVarObject *,
+PyAPI_FUNC(PyObject *) PyObject_Init(PyObject *, PyTypeObject *);
+PyAPI_FUNC(PyVarObject *) PyObject_InitVar(PyVarObject *,
                                                  PyTypeObject *, int);
-extern DL_IMPORT(PyObject *) _PyObject_New(PyTypeObject *);
-extern DL_IMPORT(PyVarObject *) _PyObject_NewVar(PyTypeObject *, int);
+PyAPI_FUNC(PyObject *) _PyObject_New(PyTypeObject *);
+PyAPI_FUNC(PyVarObject *) _PyObject_NewVar(PyTypeObject *, int);
 
 #define PyObject_New(type, typeobj) \
 		( (type *) _PyObject_New(typeobj) )
@@ -235,7 +235,7 @@
 #define PyObject_IS_GC(o) (PyType_IS_GC((o)->ob_type) && \
 	((o)->ob_type->tp_is_gc == NULL || (o)->ob_type->tp_is_gc(o)))
 
-extern DL_IMPORT(PyVarObject *) _PyObject_GC_Resize(PyVarObject *, int);
+PyAPI_FUNC(PyVarObject *) _PyObject_GC_Resize(PyVarObject *, int);
 #define PyObject_GC_Resize(type, op, n) \
 		( (type *) _PyObject_GC_Resize((PyVarObject *)(op), (n)) )
 
@@ -286,12 +286,12 @@
 	g->gc.gc_next = NULL; \
     } while (0);
 
-extern DL_IMPORT(PyObject *) _PyObject_GC_Malloc(size_t);
-extern DL_IMPORT(PyObject *) _PyObject_GC_New(PyTypeObject *);
-extern DL_IMPORT(PyVarObject *) _PyObject_GC_NewVar(PyTypeObject *, int);
-extern DL_IMPORT(void) PyObject_GC_Track(void *);
-extern DL_IMPORT(void) PyObject_GC_UnTrack(void *);
-extern DL_IMPORT(void) PyObject_GC_Del(void *);
+PyAPI_FUNC(PyObject *) _PyObject_GC_Malloc(size_t);
+PyAPI_FUNC(PyObject *) _PyObject_GC_New(PyTypeObject *);
+PyAPI_FUNC(PyVarObject *) _PyObject_GC_NewVar(PyTypeObject *, int);
+PyAPI_FUNC(void) PyObject_GC_Track(void *);
+PyAPI_FUNC(void) PyObject_GC_UnTrack(void *);
+PyAPI_FUNC(void) PyObject_GC_Del(void *);
 
 #define PyObject_GC_New(type, typeobj) \
 		( (type *) _PyObject_GC_New(typeobj) )