tty: omit need_resched() before cond_resched()

There's no need to call need_resched() because cond_resched() will do
nothing if need_resched() returns false.

Signed-off-by: Mikulas Patocka <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/tty/tty_buffer.c

···
 		if (!rcvd)
 			break;
 
-		if (need_resched())
-			cond_resched();
+		cond_resched();
 	}
 
 	mutex_unlock(&buf->lock);