LU-10073 tests: re-enable lnet selftest smoke test 4.4+ kernels

LU-10073 tests: re-enable lnet selftest smoke test 4.4+ kernels

LNet selftest smoke test was at one time failing for kernels
4.4+. My testing on newer Ubuntu 5.X kernels shows this is now
working so re-enable it in general on the x86 platform.

Test-Parameters: trivial testlist=lnet-selftest

Change-Id: I865ffa868d05c22f2cf53c5e978ab8be9e450e99
Signed-off-by: James Simmons <jsimmons@infradead.org>
Reviewed-on: https://review.whamcloud.com/46037
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: xinliang <xinliang.liu@linaro.org>
Reviewed-by: James Nunez <jnunez@whamcloud.com>
Reviewed-by: Chris Horn <chris.horn@hpe.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>