WIRE_HOWMANY versus WIRE_INTERFACES_COUNT

[PaulStoffregen]

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:

ArduinoCore-renesas/variants/NANOR4/pins_arduino.h

Line 120 in f781844

#define WIRE_HOWMANY 2

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.

[leonardocavagnis]

Thanks!
PR opened :)