pppol2tp: calls unregister_pernet_gen_device() at unload time
pppol2tp: calls unregister_pernet_gen_device() at unload time

Failure to call unregister_pernet_gen_device() can exhaust memory
if module is loaded/unloaded many times.

Signed-off-by: Eric Dumazet <a0baddf32b28d2f9429941ed4af2fe636e210591@gmail.com>
Acked-by: Cyrill Gorcunov <7a1ea01eee6961eb1e372e3508c2670446d086f4@openvz.org>
Signed-off-by: David S. Miller <fe08d3c717adf2ae63592e4c9aec6e3e404d8e3e@davemloft.net>

KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs