dns/dnsmasq: update to 2.81, unlink dnsmasq-devel

Update dns/dnsmasq to the new upstream version 2.81.
The Makefile has been rearranged with portfmt, except the
LDFLAGS+=..._intllibs... line that portfmt does not recognize.

Changelog:
http://thekelleys.org.uk/gitweb/?p=dnsmasq.git;a=blob;f=CHANGELOG;h=60b08d015b2d5a979f39b8ad43633b419135cb64;hb=7ddb99d251c3f5870c8c308a98bb8f283c831872#l1
(or see CHANGELOG in the package)

Unlink dnsmasq-devel from the build, but keep the sources,
and mark it IGNORE and list dnsmasq-devel in MOVED.