qcacld-3.0: change hdd_skb_orphan to static inline

hdd_skb_orphan is currently a static function. If not used, it may cause
compilation error.
Make the function static inline.

Change-Id: I5d78f597f2f694d370dbe7631be0a7ebc8572b0d
CRs-Fixed: 2020167

core/hdd/src/wlan_hdd_softap_tx_rx.c

@@ -220,7 +220,7 @@ static inline struct sk_buff *hdd_skb_orphan(hdd_adapter_t *pAdapter,
  *
  * Return: pointer to skb structure
  */
-static struct sk_buff *hdd_skb_orphan(hdd_adapter_t *pAdapter,
+static inline struct sk_buff *hdd_skb_orphan(hdd_adapter_t *pAdapter,
 		struct sk_buff *skb) {
 
 	struct sk_buff *nskb;

core/hdd/src/wlan_hdd_tx_rx.c

@@ -289,7 +289,7 @@ void hdd_get_tx_resource(hdd_adapter_t *adapter,
  *
  * Return: pointer to skb structure
  */
-static struct sk_buff *hdd_skb_orphan(hdd_adapter_t *pAdapter,
+static inline struct sk_buff *hdd_skb_orphan(hdd_adapter_t *pAdapter,
 		struct sk_buff *skb) {
 
 	struct sk_buff *nskb;