[NET]: Fix setsockopt locking bug

On Sparc, SO_DONTLINGER support resulted in sock_reset_flag being 
called without lock_sock().

Signed-off-by: Kyle Moffett <mrmacman_g4@mac.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/core/sock.c b/net/core/sock.c
index 8b35ccd..12f6d9a 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -206,13 +206,14 @@
 	 */
 
 #ifdef SO_DONTLINGER		/* Compatibility item... */
-	switch (optname) {
-		case SO_DONTLINGER:
-			sock_reset_flag(sk, SOCK_LINGER);
-			return 0;
+	if (optname == SO_DONTLINGER) {
+		lock_sock(sk);
+		sock_reset_flag(sk, SOCK_LINGER);
+		release_sock(sk);
+		return 0;
 	}
-#endif	
-		
+#endif
+	
   	if(optlen<sizeof(int))
   		return(-EINVAL);