Snippets for cimg 4.0.3 from Fedora s390x

Sourced from https://kojipkgs.fedoraproject.org/packages/CImg/4.0.3/2.fc45/data/logs/s390x/build.log.

• ../CImg.h:46832:33: warning: variable ‘nyi’ set but not used [-Wunused-but-set-variable=]
  

• ../plugins/nlmeans.h:109:25: warning: variable ‘n’ set but not used [-Wunused-but-set-variable=]
    109 |                     int n = 0;
        |                         ^
  

• ../plugins/nlmeans.h:167:21: warning: variable ‘n’ set but not used [-Wunused-but-set-variable=]
    167 |                 int n = 0;
        |                     ^