Make macro name more explicit, use official product name

Author: maxgerhardt

libraries/OPAMP/src/OPAMP.cpp

@@ -82,7 +82,7 @@ bool OpampClass::begin() {
 }
 
 bool OpampClass::begin(OpampSpeedMode speed) {
-    return this->begin(1u << ARDUINO_DEFAULT_OPAMP_CHANNEL, speed);
+    return this->begin(1u << ARDUINO_UNO_R4_DEFAULT_OPAMP_CHANNEL, speed);
 }
 
 bool OpampClass::begin(uint8_t const channel_mask, OpampSpeedMode speed) {

libraries/OPAMP/src/OPAMP.h

@@ -12,11 +12,11 @@ enum OpampSpeedMode {
 
 /* The supported boards have 4 OPAMP channels, however, only channel 0 is accessible. */
 /* All other channels are connected to the LED matrix or not exposed. */
-#define ARDUINO_DEFAULT_OPAMP_CHANNEL 0
+#define ARDUINO_UNO_R4_DEFAULT_OPAMP_CHANNEL 0
 
 /**
  * Pin Mapping for OPAMP
- * Uno R4 (Minima, WiFi):
+ * Arduino UNO R4 (Minima, WiFi):
  * ~Channel 0~
  *  Plus: Analog A1 (Renesas P0.00)
  *  Minus: Analog A2 (Renesas P0.01)