MLBEDSW-10299: Size types and allocator fixes for ordered_map
- Normalise the sized types used by ordered_map to present an interface more consistent with the standard library.
- Set initial allocation to zero such that declaring an empty map allocates no storage, and add tests for the same. Storage is now allocated on first-use.
- Fix potential range issue with initial hashtable size being greater than the chosen indexer.
- Fix issue where it was not possible to resize up to the maximum indexer limit.
Signed-off-by: Philip Hall philip.hall@arm.com Change-Id: I12742431808d73625ac6bcdbd7b701b52f763834