boot cfg: Allow Launching UMS from boot.

By using `BOOT_CFG_AUTOBOOT_EN` in `boot_cfg` and `EXTRA_CFG_NYX_UMS` in `extra_cfg` you can launch UMS from boot.

The `ums` variable must be populated with one of the following:

```
NYX_UMS_SD_CARD      0
NYX_UMS_EMMC_BOOT0   1
NYX_UMS_EMMC_BOOT1   2
NYX_UMS_EMMC_GPP     3
NYX_UMS_EMUMMC_BOOT0 4
NYX_UMS_EMUMMC_BOOT1 5
NYX_UMS_EMUMMC_GPP   6
```

nyx/nyx_gui/frontend/gui_tools.h

@@ -22,6 +22,7 @@
 lv_obj_t *ums_mbox;
 
 void create_tab_tools(lv_theme_t *th, lv_obj_t *parent);
+void nyx_run_ums(void *param);
 void sept_run_dump(void *param);
 bool get_autorcm_status(bool change);
 lv_res_t action_ums_sd(lv_obj_t *btn);