Bug#787431: freemat: remove bogus Build-Depends on libffcall1-dev

[Edmund Grimley Evans]

Source: freemat
Version: 4.0-5

Is there a good reason that this package Build-Depends on libffcall1-dev?

Note that the binary "freemat" package does not depend on libffcall1.

I built freemat on amd64 then rebuilt it after uninstalling libffcall1
and libffcall1-dev and found no significant differences between the
two versions of freemat_4.0-5_amd64.deb thus obtained. (Stupidly I
used a different build root for the two builds, which confused the
comparison. Don't do that if you repeat the experiment.)

Perhaps I've missed something - "ffcall" is mentioned in a few places
in the source - but if it is just a historical remnant, please remove
the build dependency so that freemat can be built on architectures
which do not have ffcall. Thanks!