tiff "broken" after switch from autotools to cmake

Hello,

With the upgrade to 4.7.0 of tiff, we have switch from autotools to cmake
system build system.

We are the only non windows platform using the cmake build system apparently
and the reason for the switch was not exposed in the build log, so I don't know
why we did it...

One of the result if the switch is it installs some new lib/cmake/* files. and
interresting fact it breaks FindTIFF.cmake provided by cmake-core.

Checking elswhere I can see noone is providing those lib/cmake files.

What is actually broken: FindTiff.cmake uses the lib/cmake package if it finds
it otherwise do some regular path checking.

One of the feature that is not implemented by lib/cmake things provided by the
tiff packages is the Optional COMPONENTS CXX.

I know nothing about libtiff or cmake, but my understanding is we should either
fix the lib/cmake thing to it provides the CXX components (imho thise should be
done upstream) or not provide at all the lib/cmake files for tiff until the
upstream have fixed them.

My second question is why did we switch to cmake building in the first place ?
Looking at the patch that were needed to be provided it is clearly not a first
class citizen to build tiff on unix like.

Best regards,
Bapt