[qca-nss-drv] Added kernel define for IPv6

Added __KERNEL__ macro to isolate the code which is only used by
kernel space.

Change-Id: Ie30fb540787168dcd0a57ee2c846e59e7f647c1e
Signed-off-by: mandrw <mandrw@codeaurora.org>
diff --git a/exports/nss_ipv6.h b/exports/nss_ipv6.h
index 3c1131c..cb84982 100644
--- a/exports/nss_ipv6.h
+++ b/exports/nss_ipv6.h
@@ -470,6 +470,8 @@
 
 extern int nss_ipv4_conn_cfg;
 
+#ifdef __KERNEL__
+
 /**
  * @brief Return the maximum number of IPv6 connections that the NSS acceleration engine supports
  *
@@ -561,4 +563,5 @@
  * @return 0 on success
  */
 extern int nss_ipv6_update_conn_count(int ipv6_num_conn);
+#endif
 #endif /* __NSS_IPV6_H */