examples: codecparser: fix compiler warnings for unstable API use

Breaks build bots and build with --werror
3 jobs for meson-examples-fix-build in 4 minutes and 3 seconds (queued for 1 second)
Status Name Job ID Coverage
  Preparation
passed manifest #49406

00:00:20

 
  Build
passed build fedora x86_64 #49407

00:01:19

 
  Full Builds
passed build android arm64 api28 #49408

00:02:22