g++ compiler issued some errors like "invalid conversion from void* to *struct nl_attr"
when compiling cpp file which calls libnl-tiny functions. (it's OK with gcc)
Also see https://dev.openwrt.org/ticket/7854
Patch from: kentarou matsuyama <matsuyama@thinktube.com>
git-svn-id: svn://svn.openwrt.org/openwrt/trunk@25101 3c298f89-4303-0410-b956-a3cf2f4a3e73