Unused function and unused variable

[tbnobody]

When compiling with higher warning levels (-Wall -Wextra -Wunused) I receive the following warn message (or error message when compiling with -Werror

Compiling .pio\build\generic_esp32s3_usb\lib55e\U8g2\clib\u8g2_buffer.c.o
.pio/libdeps/generic_esp32s3_usb/U8g2/src/clib/mui.c:591:16: warning: 'mui_task_read_nth_selectable_field' defined but not used [-Wunused-function]
 static uint8_t mui_task_read_nth_selectable_field(mui_t *ui)
                ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Compiling .pio\build\generic_esp32s3_usb\lib55e\U8g2\clib\u8g2_button.c.o
Compiling .pio\build\generic_esp32s3_usb\lib55e\U8g2\clib\u8g2_circle.c.o
.pio/libdeps/generic_esp32s3_usb/U8g2/src/clib/mui_u8g2.c: In function 'mui_u8g2_s8_vmm_draw_wm_pf':
.pio/libdeps/generic_esp32s3_usb/U8g2/src/clib/mui_u8g2.c:1256:9: warning: unused variable 's' [-Wunused-variable]
   char *s = buf;
         ^

I know it's not really a issue but it prevents from compiling with -Werror

[olikraus]

Thanks, assigned to next release