Compilation fails for any board without `Wire1` object

[per1234]

Describe the problem

For the convenience of the user, the library defines a global LTR381RGBClass instance:

Arduino_LTR381RGB/src/LTR381RGB.cpp

Line 578 in 1994245

LTR381RGBClass RGB(Wire1, LTR381RGB_ADDRESS);

This definition makes the unwarranted assumption that a Wire1 object will always be defined.

🐛 The library (and even more impactful, the Arduino_Modulino library) fails to compile for any board for which a Wire1 object is not defined.

To reproduce

1. Create a sketch with the following content:

   #include <Arduino_LTR381RGB.h>
   void setup() {}
   void loop() {}

2. Select Tools > Board > Arduino SAMD Boards (32-bits ARM Cortex-M0+) > Arduino Nano 33 IoT from the Arduino IDE menus.
   ⓘ Nano 33 IoT was chosen arbitrarily for the purposes of the demo. Note that this board is included in the Modulino Light compatibility list.
3. Select Sketch > Verify/Compile from the Arduino IDE menus.

🐛 Compilation fails:

c:\Users\per\Documents\Arduino\libraries\Arduino_LTR381RGB\src\LTR381RGB.cpp: At global scope:
c:\Users\per\Documents\Arduino\libraries\Arduino_LTR381RGB\src\LTR381RGB.cpp:578:20: error: 'Wire1' was not declared in this scope
 LTR381RGBClass RGB(Wire1, LTR381RGB_ADDRESS);
                    ^~~~~
c:\Users\per\Documents\Arduino\libraries\Arduino_LTR381RGB\src\LTR381RGB.cpp:578:20: note: suggested alternative: 'Wire'
 LTR381RGBClass RGB(Wire1, LTR381RGB_ADDRESS);
                    ^~~~~
                    Wire

Arduino_LTR381RGB version

1994245

Additional context

I noticed that, at least in some cores (I didn't do a comprehensive survey to determine how much consistency there is across the ecosystem as a whole), there is a WIRE_INTERFACES_COUNT macro:

https://github.com/arduino/ArduinoCore-samd/blob/v1.6.1/variants/arduino_zero/variant.h#L141

This might be used to determine the correct object to use in the global LTR381RGBClass instance:

#if defined(WIRE_INTERFACES_COUNT)
#if WIRE_INTERFACES_COUNT == 1
LTR381RGBClass RGB(Wire, LTR381RGB_ADDRESS);
#else // WIRE_INTERFACES_COUNT == 1
LTR381RGBClass RGB(Wire1, LTR381RGB_ADDRESS);
#endif  // WIRE_INTERFACES_COUNT == 1
#endif  // defined(WIRE_INTERFACES_COUNT)

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Originally reported at https://forum.arduino.cc/t/arduino-moduilino-lib-examples-not-compiling/1419606