OpenJPEG 2.3 installs its headers to /usr/include/openjpeg-2.3. However, since libopenjp2.pc seems to provide the right includedir CFLAGS at least since version 2.1, instead of adding yet another version check, just remove the subdir and the check for 2.2. https://bugzilla.gnome.org/show_bug.cgi?id=788703