Update Doxygen comments for some headers (#20194)

quantum/digitizer.h

@@ -13,17 +13,15 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 #pragma once
 
-#include "quantum.h"
-
 #include <stdbool.h>
-#include <stdint.h>
 
 /**
- * \defgroup digitizer
+ * \file
  *
- * HID Digitizer
+ * defgroup digitizer HID Digitizer
  * \{
  */