[Keyboard] Fix the order of underglow LEDs on ergodash/rev1 (#7791)

On the v1.2 PCB the slave half leds go in reverse order compared to the master half.
With this change, the leds are all in order from left to right, so animations like
Knight Rider look like you'd expect.

keyboards/ergodash/rev1/config.h

@@ -69,6 +69,10 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #define RGBLIGHT_SPLIT
 #define RGBLED_SPLIT { 12, 12 }    // Number of LEDs
 
+// The LEDs on the slave half go in reverse order
+#define RGBLIGHT_LED_MAP { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11, \
+                          23, 22, 21, 20, 19, 18, 17, 16, 15, 14, 13, 12}
+
 #define SOFT_SERIAL_PIN D0
 #define SELECT_SOFT_SERIAL_SPEED 1
 /*Sets the protocol speed when using serial communication*/