[lldb] Treat RangeDataVector as an augmented binary search tree

Summary:
Since RangeDataVector is assumed to always be sorted we can treat it as
an flattened BST and augment it with additional information about the
ranges belonging to each "subtree". By storing the maximum endpoint in
every subtree we can query for intervals in O(log n) time.

Reviewers: labath, teemperor

Reviewed By: labath

Subscribers: jarin, JDevlieghere, lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D74759