Arduino SAMD and SAM boards have long defined WIRE_INTERFACES_COUNT in their variant header files.

This platform defines WIRE_HOWMANY to serve the same purpose. For example:

Please consider either changing WIRE_HOWMANY to WIRE_INTERFACES_COUNT for consistency with Arduino's other boards, or also define WIRE_INTERFACES_COUNT so programs like a Scanner example which scans all Wire ports can depend on a consistent define.