qcacmn: Fix unknown symbol error when FEATURE_TSO is disabled

__qdf_nbuf_get_tso_num_seg is defined under FEATURE_TSO but declared in header
file without FEATURE_TSO. Compilation can be successful when FEATURE_TSO is
disabled but there is unknown symbol error in driver loading.
Add fix to resolve this issue.

Change-Id: Ie01875405d65a0f43221cbfd42940747de0df916
CRs-Fixed: 2007179

qdf/linux/src/i_qdf_nbuf.h

@@ -1073,8 +1073,17 @@ void __qdf_nbuf_unmap_tso_segment(qdf_device_t osdev,
 			  struct qdf_tso_seg_elem_t *tso_seg,
 			  bool is_last_seg);
 
+#ifdef FEATURE_TSO
 uint32_t __qdf_nbuf_get_tso_num_seg(struct sk_buff *skb);
 
+#else
+static inline uint32_t __qdf_nbuf_get_tso_num_seg(struct sk_buff *skb)
+{
+	return 0;
+}
+
+#endif /* FEATURE_TSO */
+
 static inline bool __qdf_nbuf_is_tso(struct sk_buff *skb)
 {
 	if (skb_is_gso(skb) &&