Handle Irrlicht limitation on the number of vertices rendered

[mebbaid]

Some models with particularly "dense" meshes in terms of number of vertices computed throw the following error when calling the idyntree-yarp-visualizer -m model.urdf

Too many vertices for 16bit index type, render artifacts may occur

This can be traced to this line https://github.com/zaki/irrlicht/blob/97472da9c22ae4a49dfcefb9da5156601fa6a82a/source/Irrlicht/CNullDriver.cpp#L808 upstream

This may lead to rendering models with missing parts/meshes.

[mebbaid]

Related PR is open in #1139

[traversaro]

Fixed by @mebbaid in #1139 .