lwtunnel: remove unused but set variable

silences the below warning:
net/core/lwtunnel.c: In function ‘lwtunnel_valid_encap_type_attr’:
net/core/lwtunnel.c:165:17: warning: variable ‘nla’ set but not used
[-Wunused-but-set-variable]

Fixes: 9ed59592e3 ("lwtunnel: fix autoload of lwt modules")
Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/core/lwtunnel.c

@@ -162,7 +162,6 @@ int lwtunnel_valid_encap_type_attr(struct nlattr *attr, int remaining)
 	struct rtnexthop *rtnh = (struct rtnexthop *)attr;
 	struct nlattr *nla_entype;
 	struct nlattr *attrs;
-	struct nlattr *nla;
 	u16 encap_type;
 	int attrlen;
 
@@ -170,7 +169,6 @@ int lwtunnel_valid_encap_type_attr(struct nlattr *attr, int remaining)
 		attrlen = rtnh_attrlen(rtnh);
 		if (attrlen > 0) {
 			attrs = rtnh_attrs(rtnh);
-			nla = nla_find(attrs, attrlen, RTA_ENCAP);
 			nla_entype = nla_find(attrs, attrlen, RTA_ENCAP_TYPE);
 
 			if (nla_entype) {