archivers/szip license

[Jason Bacon <outpaddling%yahoo.com@localhost>]

I think the license restrictions listed in Makefile are wrong:

https://support.hdfgroup.org/doc_resource/SZIP/Commercial_szip.html

I don't see anything to indicate that it cannot be redistributed in 
binary form, only that certain types of commercial use are not allowed 
without permission.

Any objections to changing it so we can generate binary packages?