Building w/ Clang 17 fails w/
```
C:/_/B/src/libheif-1.17.6/libheif/plugins/encoder_kvazaar.cc:480:12: error: variable 'kvzChroma' is used uninitialized whenever 'if' condition is false [-Werror,-Wsometimes-uninitialized]
    480 |   else if (chroma == heif_chroma_444) {
        |            ^~~~~~~~~~~~~~~~~~~~~~~~~
  C:/_/B/src/libheif-1.17.6/libheif/plugins/encoder_kvazaar.cc:[544](https://github.com/msys2/MINGW-packages/actions/runs/7408100857/job/20155643547#step:11:545):45: note: uninitialized use occurs here
    544 |   kvz_picture* pic = api->picture_alloc_csp(kvzChroma, encoded_width, encoded_height);
        |                                             ^~~~~~~~~
  C:/_/B/src/libheif-1.17.6/libheif/plugins/encoder_kvazaar.cc:480:8: note: remove the 'if' if its condition is always true
  
    480 |   else if (chroma == heif_chroma_444) {
  
        |        ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  
  C:/_/B/src/libheif-1.17.6/libheif/plugins/encoder_kvazaar.cc:456:3: note: variable 'kvzChroma' is declared here
  
    456 |   kvz_chroma_format kvzChroma;
  
        |   ^
  
  1 error generated.
```
error: variable 'kvzChroma' is used uninitialized
This is a GitHub Issue
repo:libheif
owner:strukturag
Title : error: variable 'kvzChroma' is used uninitialized
Issue date:

--- start body ---
Building w/ Clang 17 fails w/
```
C:/_/B/src/libheif-1.17.6/libheif/plugins/encoder_kvazaar.cc:480:12: error: variable 'kvzChroma' is used uninitialized whenever 'if' condition is false [-Werror,-Wsometimes-uninitialized]
    480 |   else if (chroma == heif_chroma_444) {
        |            ^~~~~~~~~~~~~~~~~~~~~~~~~
  C:/_/B/src/libheif-1.17.6/libheif/plugins/encoder_kvazaar.cc:[544](https://github.com/msys2/MINGW-packages/actions/runs/7408100857/job/20155643547#step:11:545):45: note: uninitialized use occurs here
    544 |   kvz_picture* pic = api->picture_alloc_csp(kvzChroma, encoded_width, encoded_height);
        |                                             ^~~~~~~~~
  C:/_/B/src/libheif-1.17.6/libheif/plugins/encoder_kvazaar.cc:480:8: note: remove the 'if' if its condition is always true
  
    480 |   else if (chroma == heif_chroma_444) {
  
        |        ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  
  C:/_/B/src/libheif-1.17.6/libheif/plugins/encoder_kvazaar.cc:456:3: note: variable 'kvzChroma' is declared here
  
    456 |   kvz_chroma_format kvzChroma;
  
        |   ^
  
  1 error generated.
```
--- end body ---

The issue indicates that the variable 'kvzChroma' in the encoder_kvazaar.cc file is being used without being initialized, which can lead to undefined behavior. This is a coding error that could potentially lead to security vulnerabilities if the uninitialized variable is used in a way that affects program logic or memory access.