riemann-c-client: fix build on bfin
Fixes:
http://autobuild.buildroot.net/results/8de/
8de7e533fed3c48fdbe164bc9286148e63494c8f/build-end.log
http://autobuild.buildroot.net/results/828/
828a4e09cb14c33b021bd347394104ff8b6dba78/build-end.log
http://autobuild.buildroot.net/results/fc8/
fc80326880fb19cd6fbd6c0073916373a52ef873/build-end.log
LD symbol versioning is not working on blackfin even though ld accepts the
--version-script argument, causing link errors, so disable it.
Notice: These autobuilder issues happened with an external fdpic toolchain,
but the issue also occurs with internal toolchain / binutils 2.27 and
fdpic/flat.
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>