package/libasplib: fix build error on m68k

package/libasplib: fix build error on m68k

Patch written by Waldemar Brodkorb:
http://lists.busybox.net/pipermail/buildroot/2016-November/177726.html

This patch however did not work: "Unfortunately libasplib cmake
infrastructure ignores my CMAKE_CXX_FLAGS."

To make this patch work libasplib needed to be bumped because the cmake
infrastructure was updated back in August 2016 which fixed the problem:
https://github.com/AchimTuran/asplib/commit/6326d1f5e8dad9fd9947b7f4688ddddda91e9e9e

Signed-off-by: Bernd Kuhls <bernd.kuhls@t-online.de>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>