Addressed void* return warning in all keymaps

quantum/matrix.c

@@ -48,14 +48,14 @@ static void unselect_rows(void);
 static void select_row(uint8_t row);
 
 __attribute__ ((weak))
-void * matrix_init_kb(void) {
+void matrix_init_kb(void) {
 
-};
+}
 
 __attribute__ ((weak))
-void * matrix_scan_kb(void) {
+void matrix_scan_kb(void) {
 
-};
+}
 
 inline
 uint8_t matrix_rows(void)
@@ -86,9 +86,7 @@ void matrix_init(void)
         matrix_debouncing[i] = 0;
     }
 
-    if (matrix_init_kb) {
-        (*matrix_init_kb)();
-    }
+    matrix_init_kb();
 }
 
 
@@ -152,9 +150,7 @@ uint8_t matrix_scan(void)
     }
 #endif
 
-    if (matrix_scan_kb) {
-        (*matrix_scan_kb)();
-    }
+    matrix_scan_kb();
 
     return 1;
 }