Add note about SDO line

(leave TFT SDO disconnected if other SPI devices share MISO)

User_Setups/Setup20_ILI9488.h

@@ -53,7 +53,7 @@
 // We must use hardware SPI, a minimum of 3 GPIO pins is needed.
 // Typical setup for ESP8266 NodeMCU ESP-12 is :
 //
-// Display SDO/MISO  to NodeMCU pin D6 (or leave disconnected if not reading TFT)
+// Display SDO/MISO  to NodeMCU pin D6 (leave TFT SDO disconnected if other SPI devices share MISO)
 // Display LED       to NodeMCU pin VIN (or 5V, see below)
 // Display SCK       to NodeMCU pin D5
 // Display SDI/MOSI  to NodeMCU pin D7
@@ -114,7 +114,7 @@
 // For ESP32 Dev board (only tested with ILI9341 display)
 // The hardware SPI can be mapped to any pins
 
-//#define TFT_MISO 19
+//#define TFT_MISO 19 //  (leave TFT SDO disconnected if other SPI devices share MISO)
 //#define TFT_MOSI 23
 //#define TFT_SCLK 18
 //#define TFT_CS    15  // Chip select control pin