math/asymptote: add pkg-message for asymptote's rendering issue in 3D

Asymptote with enabled hardware acceleration produces incorrect rendered
figures in 3D. It is proven that asy has problems with the xf86-video-intel
driver.

To successfully process 3D figures or examples, it is necessary to always
use software rendering.

% env LIBGL_ALWAYS_SOFTWARE=1 asy sample.asy

PR: 229043
Submitted by: cpm
Approved by: nivit (maintainer timeout, 2 weeks)