You really don't have to do English lit. / history.
I had this dilemma last year before picking my A-level subjects for law.
Basically, what you need is good, strong and above all, academically rigorous subjects. This includes the tougher essay based subjects like RS (philosophy + ethics), history, English lit. etc.. It also includes mathematics, pure sciences (phys/chem/bio) and modern foreign languages.
It is best to get a mix out of these but also to focus on what you are good at and can manage, don't over-challenge yourself unless you are confident you can manage it.
I'm doing maths, 2 sciences and 2 essay-based subjects with the aspiration to read law at a good university too. Granted, I do one subject out of English lit. and history, but don't be bullied into doing so if you don't feel like you'll be able to perform well. Remember, law is very competitive and at the top-universities, anything below A grades at AS is bad!