cogl: remove CoglFuncPtr, use GCallback instead

They literally mean the same thing, so we shouldn't reinvent the wheel.

cogl/cogl/cogl-types.h

@@ -125,15 +125,6 @@ cogl_handle_ref (CoglHandle handle);
 void
 cogl_handle_unref (CoglHandle handle);
 
-/**
- * CoglFuncPtr:
- *
- * The type used by cogl for function pointers, note that this type
- * is used as a generic catch-all cast for function pointers and the
- * actual arguments and return type may be different.
- */
-typedef void (* CoglFuncPtr) (void);
-
 /* We forward declare this in cogl-types to avoid circular dependencies
  * between cogl-matrix.h, cogl-euler.h and cogl-quaterion.h */
 typedef struct _CoglMatrix      CoglMatrix;

cogl/cogl/cogl.c

@@ -59,7 +59,7 @@
 
 #include "deprecated/cogl-framebuffer-deprecated.h"
 
-CoglFuncPtr
+GCallback
 cogl_get_proc_address (const char* name)
 {
   _COGL_GET_CONTEXT (ctx, NULL);

cogl/cogl/cogl1-context.h

@@ -106,7 +106,7 @@ cogl_features_available (CoglFeatureFlags features);
  * Return value: a pointer to the requested function or %NULL if the
  *   function is not available.
  */
-CoglFuncPtr
+GCallback
 cogl_get_proc_address (const char *name);
 
 /**

cogl/cogl/winsys/cogl-winsys-egl.c

@@ -138,7 +138,7 @@ get_error_string (void)
   }
 }
 
-static CoglFuncPtr
+static GCallback
 _cogl_winsys_renderer_get_proc_address (CoglRenderer *renderer,
                                         const char *name,
                                         CoglBool in_core)

cogl/cogl/winsys/cogl-winsys-glx.c

@@ -166,7 +166,7 @@ static const CoglFeatureData winsys_feature_data[] =
 #include "winsys/cogl-winsys-glx-feature-functions.h"
   };
 
-static CoglFuncPtr
+static GCallback
 _cogl_winsys_renderer_get_proc_address (CoglRenderer *renderer,
                                         const char *name,
                                         CoglBool in_core)

cogl/cogl/winsys/cogl-winsys-private.h

@@ -79,7 +79,7 @@ typedef struct _CoglWinsysVtable
 
   /* Required functions */
 
-  CoglFuncPtr
+  GCallback
   (*renderer_get_proc_address) (CoglRenderer *renderer,
                                 const char *name,
                                 CoglBool in_core);

cogl/cogl/winsys/cogl-winsys-stub.c

@@ -49,7 +49,7 @@ static int _cogl_winsys_stub_dummy_ptr;
  * integration code.
  */
 
-static CoglFuncPtr
+static GCallback
 _cogl_winsys_renderer_get_proc_address (CoglRenderer *renderer,
                                         const char *name,
                                         CoglBool in_core)