Fixing make distcheck openexr issue

This solves the problem of distcheck failing due to openexr being a conditional subdir build.

1. Add AM_CONDITIONAL to configure.in after AM_PATH_OPENEXR.

AM_PATH_OPENEXR(have_openexr=yes OPENEXR=openexr, have_openexr=no OPENEXR= )

AM_CONDITIONAL(HAVE_OPENEXR, test x$have_openexr = xyes)

1. Do NOT make openexr conditional in plug-ins/Makefile.am. Do not use DIST_SUBDIRS or DISTCLEANFILES.

SUBDIRS = \ blur \ openexr \ unsharp

## SUBDIRS = \ ## blur \ ## @OPENEXR@ \ ## unsharp

## DIST_SUBDIRS = $(SUBDIRS)

## DISTCLEANFILES = openexr/Makefile openexr/.deps/openexr.Po

1. Wrap plug-ins/openexr/Makefile.am with conditional:

if HAVE_OPENEXR

pluginlibdir = $(programplugindir)/plug-ins

pluginlib_PROGRAMS = openexr

openexr_SOURCES = openexr.cxx

endif

--- output ---

=================================================

cinepaint-0.18-2.tar.gz is ready for distribution =================================================