mbuf: fix C++ compatibility by making sched struct visible

Although C compilation works with the struct rte_mbuf_sched
declared inside the struct rte_mbuf namespace, C++ fails to
compile. This fix moves the rte_mbuf_sched struct up to the
global namespace, instead of declaring it inside the struct
mbuf namespace.

The struct rte_mbuf_sched is being used on the stack in
rte_mbuf_sched_get() and as a cast in _set(). For this
reason, it must be exposed as an available type.

Fixes: 5d3f72100904 ("mbuf: implement generic format for sched field")

Signed-off-by: Harry van Haaren <harry.van.haaren@intel.com>
Acked-by: Cristian Dumitrescu <cristian.dumitrescu@intel.com>
Acked-by: Olivier Matz <olivier.matz@6wind.com>

lib/librte_mbuf/rte_mbuf.h

@@ -468,6 +468,17 @@ __extension__
 typedef uint64_t MARKER64[0]; /**< marker that allows us to overwrite 8 bytes
                                * with a single assignment */
 
+struct rte_mbuf_sched {
+	uint32_t queue_id;   /**< Queue ID. */
+	uint8_t traffic_class;
+	/**< Traffic class ID. Traffic class 0
+	 * is the highest priority traffic class.
+	 */
+	uint8_t color;
+	/**< Color. @see enum rte_color.*/
+	uint16_t reserved;   /**< Reserved. */
+}; /**< Hierarchical scheduler */
+
 /**
  * The generic rte_mbuf, containing a packet mbuf.
  */
@@ -574,16 +585,8 @@ struct rte_mbuf {
 				 * on PKT_RX_FDIR_* flag in ol_flags.
 				 */
 			} fdir;	/**< Filter identifier if FDIR enabled */
-			struct rte_mbuf_sched {
+			struct rte_mbuf_sched sched;
-				uint32_t queue_id;   /**< Queue ID. */
+			/**< Hierarchical scheduler : 8 bytes */
-				uint8_t traffic_class;
-				/**< Traffic class ID. Traffic class 0
-				 * is the highest priority traffic class.
-				 */
-				uint8_t color;
-				/**< Color. @see enum rte_color.*/
-				uint16_t reserved;   /**< Reserved. */
-			} sched; /**< Hierarchical scheduler */
 			struct {
 				uint32_t reserved1;
 				uint16_t reserved2;