Fix compile error with DUE + MAX6675 (#13086)

Marlin/src/libs/private_spi.h

     FORCE_INLINE static uint8_t receive() { return softSPI.receive(); }
 };
 
-
 // Hardware SPI
 template<>
 class SPIclass<MISO_PIN, MOSI_PIN, SCK_PIN> {
   public:
     FORCE_INLINE static void init() {
-        OUT_WRITE(SCK_PIN, LOW);
-        OUT_WRITE(MOSI_PIN, HIGH);
-        SET_INPUT(MISO_PIN);
-        WRITE(MISO_PIN, HIGH);
+      OUT_WRITE(SCK_PIN, LOW);
+      OUT_WRITE(MOSI_PIN, HIGH);
+      SET_INPUT_PULLUP(MISO_PIN);
     }
     FORCE_INLINE static uint8_t receive() {
-      SPDR = 0;
-      for (;!TEST(SPSR, SPIF););
-      return SPDR;
+      #if defined(__AVR__) || defined(__MK20DX256__) || defined(__MK64FX512__) || defined(__MK66FX1M0__)
+        SPDR = 0;
+        for (;!TEST(SPSR, SPIF););
+        return SPDR;
+      #else
+        return spiRec();
+      #endif
     }
-
 };

Marlin/src/module/temperature.cpp

 #include "../core/language.h"
 #include "../HAL/shared/Delay.h"
 
-#if ENABLED(HEATER_0_USES_MAX6675)
+#define MAX6675_SEPARATE_SPI (ENABLED(HEATER_0_USES_MAX6675) || ENABLED(HEATER_1_USES_MAX6675)) && PIN_EXISTS(MAX6675_SCK) && PIN_EXISTS(MAX6675_DO)
+
+#if MAX6675_SEPARATE_SPI
   #include "../libs/private_spi.h"
 #endif
 
 
 #endif
 
-#if ENABLED(HEATER_0_USES_MAX6675)
-  #ifndef MAX6675_SCK_PIN
-    #define MAX6675_SCK_PIN SCK_PIN
-  #endif
-  #ifndef MAX6675_DO_PIN
-    #define MAX6675_DO_PIN MISO_PIN
-  #endif
+#if MAX6675_SEPARATE_SPI
   SPIclass<MAX6675_DO_PIN, MOSI_PIN, MAX6675_SCK_PIN> max6675_spi;
 #endif
 
     #endif
   #endif
 
-  #if ENABLED(HEATER_0_USES_MAX6675)
+  #if MAX6675_SEPARATE_SPI
 
     OUT_WRITE(SCK_PIN, LOW);
     OUT_WRITE(MOSI_PIN, HIGH);
     OUT_WRITE(SS_PIN, HIGH);
     OUT_WRITE(MAX6675_SS_PIN, HIGH);
 
-  #endif // HEATER_0_USES_MAX6675
+  #endif
 
   #if ENABLED(HEATER_1_USES_MAX6675)
     OUT_WRITE(MAX6675_SS2_PIN, HIGH);
     //
     // TODO: spiBegin, spiRec and spiInit doesn't work when soft spi is used.
     //
-    #if MB(MIGHTYBOARD_REVE)
+    #if MAX6675_SEPARATE_SPI
       spiBegin();
       spiInit(MAX6675_SPEED_BITS);
     #endif
     max6675_temp = 0;
     for (uint8_t i = sizeof(max6675_temp); i--;) {
       max6675_temp |= (
-        #if MB(MIGHTYBOARD_REVE)
+        #if MAX6675_SEPARATE_SPI
           max6675_spi.receive()
         #else
           spiRec()