Apply suggestions by @aentinger for allowing custom pin definitions.

Author: Pedro Marquez

src/RS485.h

@@ -30,7 +30,6 @@
 #endif
 #endif
 
-#ifndef RS485_DEFAULT_DE_PIN
 #ifdef __AVR__
 #define RS485_DEFAULT_DE_PIN 2
 #define RS485_DEFAULT_RE_PIN -1
@@ -41,11 +40,19 @@
 #define RS485_DEFAULT_DE_PIN A4
 #define RS485_DEFAULT_RE_PIN A5
 #else
+#ifndef RS485_DEFAULT_DE_PIN
 #define RS485_DEFAULT_DE_PIN A6
 #define RS485_DEFAULT_RE_PIN A5
 #endif
 #endif
 
+#ifdef CUSTOM_RS485_DEFAULT_DE_PIN
+# define RS485_DEFAULT_DE_PIN CUSTOM_RS485_DEFAULT_DE_PIN
+#endif
+
+#ifdef CUSTOM_RS485_DEFAULT_RE_PIN
+# define RS485_DEFAULT_RE_PIN CUSTOM_RS485_DEFAULT_RE_PIN
+#endif
 
 #define RS485_DEFAULT_PRE_DELAY 50
 #define RS485_DEFAULT_POST_DELAY 50