ipmi:devintf: Return a proper error when recv buffer too small

The right error message wasn't being set in one location, and it would
return success on a failure.

Signed-off-by: Corey Minyard <cminyard@mvista.com>

drivers/char/ipmi/ipmi_devintf.c

@@ -247,11 +247,13 @@ static int handle_recv(struct ipmi_file_private *priv,
 
 	if (msg->msg.data_len > 0) {
 		if (rsp->msg.data_len < msg->msg.data_len) {
-			rv2 = -EMSGSIZE;
+			if (trunc) {
-			if (trunc)
+				rv2 = -EMSGSIZE;
 				msg->msg.data_len = rsp->msg.data_len;
-			else
+			} else {
+				rv = -EMSGSIZE;
 				goto recv_putback_on_err;
+			}
 		}
 
 		if (copy_to_user(rsp->msg.data,