[Debian-med-packaging] Bug#793843: kmc: FTBFS anywhere but amd64

[Aaron M. Ucko]

Source: kmc
Version: 2.0+dfsg-1
Severity: important
Justification: fails to build from source

Builds of kmc for architectures other than amd64 fail due to
inappropriate makefile settings.

First off, as reported in #793835, the makefile explicitly specifies
-m64.  On some architectures, this option is redundant; on the rest,
it is either invalid altogether or fails without extra packages
installed.

Moreover, it explicitly sets

BOOST_LIB = /usr/lib/x86_64-linux-gnu

which obviously won't work on other architectures.  The best fix is to
let the linker find the libraries itself, by specifying
-lboost_thread, etc.; however, if you must give a path, please let it
vary properly by architecture:

BOOST_LIB := $(shell dpkg-architecture -qDEB_HOST_MULTIARCH)

Thanks!