Change depricated symbol ICACHE_RAM_ATTR that had been used for the

ESP8266 this is now the same as the ESP32

src/SDI12_boards.h

@@ -19,23 +19,17 @@ sensors. This library provides a general software solution, without requiring
 #include <Arduino.h>
 
 #if defined(ESP32) || defined(ESP8266)
+// On espressif boards (ESP8266 and ESP32), the ISR must be stored in IRAM
+#define ESPFAMILY_USE_INSTRUCTION_RAM IRAM_ATTR
 /** The interger type (size) of the timer return value */
 typedef uint32_t sdi12timer_t;
-#else
-/** The interger type (size) of the timer return value */
-typedef uint8_t sdi12timer_t;
-#endif
 
-// On espressif boards (ESP8266 and ESP32), the ISR must be stored in IRAM
-#if defined(ESP32)
-#define ESPFAMILY_USE_INSTRUCTION_RAM IRAM_ATTR
-#elif defined(ESP8266)
-#define ESPFAMILY_USE_INSTRUCTION_RAM  ICACHE_RAM_ATTR
 #else
 #define ESPFAMILY_USE_INSTRUCTION_RAM
+/** The interger type (size) of the timer return value */
+typedef uint8_t sdi12timer_t;
 #endif
 
-
 /**
  * @brief The class used to define the processor timer for the SDI-12 serial emulation.
  */