[zeromq-dev] czmq and math library

[Stephen Hemminger]

libczmq is linked against math library but does not appear to use it
(at least on Linux).  Not sure about other platforms:

Debian build warning:
   dh_shlibdeps
dpkg-shlibdeps: warning: dependency on libm.so.6 could be avoided if "debian/libczmq0/usr/lib/libczmq.so.1.0.0" were not uselessly linked against it (they use none of its symbols).
   dh_installdeb