Update SPI.h

In the comments: "Teensy 3.x" changed to "Teensy LC". Or is the LC also part of the "3" family?

SPI.h

 	inline static void attachInterrupt() { }
 	inline static void detachInterrupt() { }
 
-	// Teensy 3.x can use alternate pins for these 3 SPI signals.
+	// Teensy LC can use alternate pins for these 3 SPI signals.
 	inline static void setMOSI(uint8_t pin) __attribute__((always_inline)) {
 		SPCR.setMOSI(pin);
 	}
 	inline static void attachInterrupt() { }
 	inline static void detachInterrupt() { }
 
-	// Teensy 3.x can use alternate pins for these 3 SPI signals.
+	// Teensy LC can use alternate pins for these 3 SPI signals.
 	inline static void setMOSI(uint8_t pin) __attribute__((always_inline)) {
 		SPCR1.setMOSI(pin);
 	}