fix(conf) better support bool option from Kconfign (#2555)

* fix(arc) format code

Signed-off-by: FASTSHIFT <vifextech@foxmail.com>

* fix(Kconfig) add missing LV_BUILD_EXAMPLES configuration

Signed-off-by: FASTSHIFT <vifextech@foxmail.com>

* fix(fsdrv): remove the seek call in fs_open (#2736)

since the file should be located at zero after open

Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>

* docs(os) add example and clarify some poinits

* fix(draw border):border draw error if border width > radius (#2739)

* fix(label) consider base dir lv_label_get_letter_pos in special cases

related to https://github.com/lvgl/lvgl/issues/2712#issuecomment-953463193

* improve lv_conf_internal_gen.py for better Kconfig support

Co-authored-by: Xiang Xiao <xiaoxiang@xiaomi.com>
Co-authored-by: embeddedt <42941056+embeddedt@users.noreply.github.com>
Co-authored-by: guoweilkd <guowei15@xiaomi.com>
Co-authored-by: Gabor Kiss-Vamosi <kisvegabor@gmail.com>

Kconfig

@@ -836,4 +836,8 @@ menu "LVGL configuration"
             default y if !LV_CONF_MINIMAL
     endmenu
 
+    config LV_BUILD_EXAMPLES
+        bool "Enable the examples to be built with the library."
+        default y
+
 endmenu