docs: removes non ascii characters (#4175)

docs/libs/ffmpeg.rst

@@ -25,7 +25,7 @@ Enable :c:macro:`LV_USE_FFMPEG` in ``lv_conf.h``.
 
 See the examples below.
 
-Note that, the FFmpeg extension doesn’t use LVGL’s file system. You can
+Note that, the FFmpeg extension doesn't use LVGL's file system. You can
 simply pass the path to the image or video as usual on your operating
 system or platform.
 

docs/libs/png.rst

@@ -16,7 +16,7 @@ enable one in ``lv_conf.h`` with ``LV_USE_FS_...``
 The whole PNG image is decoded so during decoding RAM equals to
 ``image width x image height x 4`` bytes are required.
 
-As it might take significant time to decode PNG images LVGL’s :ref:`image-caching` feature can be useful.
+As it might take significant time to decode PNG images LVGL's :ref:`image-caching` feature can be useful.
 
 Example
 -------

docs/libs/rlottie.rst

@@ -56,7 +56,7 @@ To create a Lottie animation from file use:
      lv_obj_t * lottie = lv_rlottie_create_from_file(parent, width, height, "path/to/lottie.json");
 
 Note that, Rlottie uses the standard STDIO C file API, so you can use
-the path “normally” and no LVGL specific driver letter is required.
+the path "normally" and no LVGL specific driver letter is required.
 
 Use Rlottie from raw string data
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
@@ -206,7 +206,7 @@ An example CMakeLists file has been provided at
 ``/env_support/esp/rlottie/CMakeLists.txt``
 
 Copy this CMakeLists file to
-``‘your-project-directory'/components/rlottie/``
+``'your-project-directory'/components/rlottie/``
 
 In addition to the component CMakeLists file, you'll also need to tell
 your project level CMakeLists in your IDF project to require rlottie:

docs/libs/sjpg.rst

@@ -12,9 +12,9 @@ Overview
 -  Supports both normal JPG and the custom SJPG formats.
 -  Decoding normal JPG consumes RAM with the size fo the whole
    uncompressed image (recommended only for devices with more RAM)
--  SJPG is a custom format based on “normal” JPG and specially made for
+-  SJPG is a custom format based on "normal" JPG and specially made for
    LVGL.
--  SJPG is ‘split-jpeg’ which is a bundle of small jpeg fragments with
+-  SJPG is 'split-jpeg' which is a bundle of small jpeg fragments with
    an sjpg header.
 -  SJPG size will be almost comparable to the jpg file or might be a
    slightly larger.
@@ -25,7 +25,7 @@ Overview
    (can be modified)
 -  Currently only 16 bit image format is supported (TODO)
 -  Only the required partion of the JPG and SJPG images are decoded,
-   therefore they can’t be zoomed or rotated.
+   therefore they can't be zoomed or rotated.
 
 Usage
 -----