keymap: Update khord let's split keymap and add chocopad keymap (#3482)

* modifications to add mouse buttons 1-4 and misc

* Add khord chocopad keymap

* fix merge message

keyboards/lets_split/keymaps/khord/config.h

@@ -25,6 +25,9 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 #define TAPPING_TERM 150
 
+/* prevent stuck modifiers */
+#define PREVENT_STUCK_MODIFIERS
+
 /* Use I2C or Serial, not both */
 
 #define USE_SERIAL