haveged: for sparc we need generic clockgettime

This fixes autobuilder error:
http://autobuild.buildroot.net/results/5b8bbc30f347140309ab2f81e1fe50f517356a3e/



As sparcv9 assembly is used, we need to enable generic clock_gettime
for sparcv8 systems.

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