Fixed pin for RGB on lets_split/sockets keyboard (#3284)

keyboards/lets_split/sockets/config.h

@@ -59,7 +59,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 )
 
 /* ws2812 RGB LED */
-#define RGB_DI_PIN D1
+#define RGB_DI_PIN D4
 #define RGBLIGHT_TIMER
 #define RGBLED_NUM 12    // Number of LEDs
 #define ws2812_PORTREG  PORTD