package/openjpeg: New package openjpeg 1.5.2

This package is needed by Poppler.

[Thomas:
 - fix download location, which was incorrect.
 - add dependency on host-pkgconf, since the configure.ac script uses
   PKG_CHECK_MODULES and we're doing an autoreconf.
 - add optional dependencies on libpng, tiff and lcms2, so that they
   are explicit instead of automatically detected.]

Signed-off-by: Olivier Schonken <olivier.schonken@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>