type_check_arith_op does not preserve non_neg and pos prefixes leading to false positives

[erszcz]

This stems from compat_arith_type returning TInteger in the general case:

compat_arith_type(Ty1, Ty2, Env) ->
    TInteger = type(integer)
    ...

even if one of Ty1 or Ty2 are more specific and the operator is +.

Test:

test() ->
    Indent = string:length("123"),
    lists:duplicate(Indent + 3, " ").

Found when typechecking OTP's argparse.erl.