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
OpenJPEG 2.2 has some API changes and thus ships its headers in a new
include path. Add a configure check (to both meson and autoconf) to
detect the newer version of OpenJPEG and add conditional includes.
Fix the autoconf test for OpenJPEG 2.1, which checked for HAVE_OPENJPEG,
which was always set even for 2.0.
https://bugzilla.gnome.org/show_bug.cgi?id=786250
The port was trivial, and according to the NEWS file nothing else has changed,
but it is possible that other API was changed without proper notification.
OpenJPEG upstream has shipped a pkg-config file for the past 4 years, and all
distros should be shipping it by now.
https://bugzilla.gnome.org/show_bug.cgi?id=766213
