clapack: disable for m68k coldfire

Either a assembler bug or a platform limitation.
Fixes:
http://autobuild.buildroot.net/results/d24a2e9b35c98a10585cd28b3306a09c49163296/



Signed-off-by: Waldemar Brodkorb <wbx@openadk.org>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>