netlink: add nl_set_extack_cookie_u32()

Similar to existing nl_set_extack_cookie_u64(), add new helper
nl_set_extack_cookie_u32() which sets extack cookie to a u32 value.

Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/netlink.h b/include/linux/netlink.h
index 205fa7b..4090524 100644
--- a/include/linux/netlink.h
+++ b/include/linux/netlink.h
@@ -119,6 +119,15 @@
 	extack->cookie_len = sizeof(__cookie);
 }
 
+static inline void nl_set_extack_cookie_u32(struct netlink_ext_ack *extack,
+					    u32 cookie)
+{
+	u32 __cookie = cookie;
+
+	memcpy(extack->cookie, &__cookie, sizeof(__cookie));
+	extack->cookie_len = sizeof(__cookie);
+}
+
 void netlink_kernel_release(struct sock *sk);
 int __netlink_change_ngroups(struct sock *sk, unsigned int groups);
 int netlink_change_ngroups(struct sock *sk, unsigned int groups);