check_tcp: Don't close connection too early

Closing the connection because the bytes received are less than the
buffer size assumes that all the bytes will be received in one go.  This
is not always true!

plugins/check_tcp.c

@@ -277,10 +277,7 @@ main (int argc, char **argv)
 			memcpy(&status[len], buffer, i);
 			len += i;
 
-			/* stop reading if user-forced or data-starved */
-			if(i < sizeof(buffer) || (maxbytes && len >= maxbytes))
-				break;
-
+			/* stop reading if user-forced */
 			if (maxbytes && len >= maxbytes)
 				break;
 		}