Convert Encoder callbacks to be boolean functions (#12805)

Co-authored-by: James Young <18669334+noroadsleft@users.noreply.github.com>

keyboards/evolv/evolv.c

@@ -17,12 +17,14 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 #include "evolv.h"
 
-__attribute__((weak)) void encoder_update_user(uint8_t index, bool clockwise) {
+bool encoder_update_kb(uint8_t index, bool clockwise) {
+    if (!encoder_update_user(index, clockwise)) return false;
     if (index == 0) { /* First encoder */
         if (clockwise) {
             tap_code(KC_VOLU);
         } else {
             tap_code(KC_VOLD);
         }
-    } 
+    }
+    return true;
 }