testSockDiag: fix false positive

Kernels above 3.8 have a different value of AF_MAX, which causes
this test to generate false positives. Don't attempt to run the
test on kernels above 3.8 as the vulnerability is already patched
on such kernels.

Bug: 17253473
Change-Id: Ic2caff9f9c3ce2ca04ee92c92ff693c35f473309
1 file changed