Revert "package/ola: drop autoreconf"

This reverts commit 66d348ae because
for an unknown reason, the build fails if autoreconf is dropped:

/home/buildroot/autobuild/instance-2/output-1/host/opt/ext-toolchain/bin/../lib/gcc/i686-buildroot-linux-uclibc/9.3.0/../../../../i686-buildroot-linux-uclibc/bin/ld: warning: libolauartdmx.so.0, needed by olad/.libs/libolaserver.so, not found (try using -rpath or -rpath-link)
/home/buildroot/autobuild/instance-2/output-1/host/opt/ext-toolchain/bin/../lib/gcc/i686-buildroot-linux-uclibc/9.3.0/../../../../i686-buildroot-linux-uclibc/bin/ld: warning: libolaserverplugininterface.so.0, needed by olad/.libs/libolaserver.so, not found (try using -rpath or -rpath-link)

Fixes:
 - http://autobuild.buildroot.org/results/f8164c69da0b9fa38081e8b785d8234f0f297ae1


Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>