cogl: Move material_copy() out of the deprecated section

We strongly suggest people should be using cogl_material_copy(), but it
was hidden behind the deprecation guards.

cogl/cogl-material.h

@@ -88,8 +88,6 @@ typedef enum {
  */
 CoglHandle cogl_material_new (void);
 
-#ifndef COGL_DISABLE_DEPRECATED
-
 /**
  * cogl_material_copy:
  *
@@ -108,6 +106,8 @@ CoglHandle cogl_material_new (void);
  */
 CoglHandle cogl_material_copy (CoglHandle source);
 
+#ifndef COGL_DISABLE_DEPRECATED
+
 /**
  * cogl_material_ref:
  * @handle: a @CoglHandle.