net: sctp: fix warning "NULL check before some freeing functions is not needed"

This patch removes NULL checks before calling kfree.

fixes below issues reported by coccicheck
net/sctp/sm_make_chunk.c:2586:3-8: WARNING: NULL check before some
freeing functions is not needed.
net/sctp/sm_make_chunk.c:2652:3-8: WARNING: NULL check before some
freeing functions is not needed.
net/sctp/sm_make_chunk.c:2667:3-8: WARNING: NULL check before some
freeing functions is not needed.
net/sctp/sm_make_chunk.c:2684:3-8: WARNING: NULL check before some
freeing functions is not needed.
Signed-off-by: Hariprasad Kelam <hariprasad.kelam@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/sctp/sm_make_chunk.c

@@ -2582,8 +2582,7 @@ static int sctp_process_param(struct sctp_association *asoc,
 	case SCTP_PARAM_STATE_COOKIE:
 		asoc->peer.cookie_len =
 			ntohs(param.p->length) - sizeof(struct sctp_paramhdr);
-		if (asoc->peer.cookie)
-			kfree(asoc->peer.cookie);
+		kfree(asoc->peer.cookie);
 		asoc->peer.cookie = kmemdup(param.cookie->body, asoc->peer.cookie_len, gfp);
 		if (!asoc->peer.cookie)
 			retval = 0;
@@ -2648,8 +2647,7 @@ static int sctp_process_param(struct sctp_association *asoc,
 			goto fall_through;
 
 		/* Save peer's random parameter */
-		if (asoc->peer.peer_random)
-			kfree(asoc->peer.peer_random);
+		kfree(asoc->peer.peer_random);
 		asoc->peer.peer_random = kmemdup(param.p,
 					    ntohs(param.p->length), gfp);
 		if (!asoc->peer.peer_random) {
@@ -2663,8 +2661,7 @@ static int sctp_process_param(struct sctp_association *asoc,
 			goto fall_through;
 
 		/* Save peer's HMAC list */
-		if (asoc->peer.peer_hmacs)
-			kfree(asoc->peer.peer_hmacs);
+		kfree(asoc->peer.peer_hmacs);
 		asoc->peer.peer_hmacs = kmemdup(param.p,
 					    ntohs(param.p->length), gfp);
 		if (!asoc->peer.peer_hmacs) {
@@ -2680,8 +2677,7 @@ static int sctp_process_param(struct sctp_association *asoc,
 		if (!ep->auth_enable)
 			goto fall_through;
 
-		if (asoc->peer.peer_chunks)
-			kfree(asoc->peer.peer_chunks);
+		kfree(asoc->peer.peer_chunks);
 		asoc->peer.peer_chunks = kmemdup(param.p,
 					    ntohs(param.p->length), gfp);
 		if (!asoc->peer.peer_chunks)