(!1956) dri3: move dri3_syncobj_type to non-public header

The symbol isn't exported, thus not accessible to modules.
No need to keep it in public header.

Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>

dri3/dri3.h

@@ -30,8 +30,6 @@
 
 #define DRI3_SCREEN_INFO_VERSION        4
 
-extern RESTYPE dri3_syncobj_type;
-
 struct dri3_syncobj
 {
     XID id;

dri3/dri3_priv.h

@@ -35,6 +35,8 @@
 
 extern DevPrivateKeyRec dri3_screen_private_key;
 
+extern RESTYPE dri3_syncobj_type;
+
 typedef struct dri3_dmabuf_format {
     uint32_t                    format;
     uint32_t                    num_modifiers;