perf auxtrace: Define auxtrace record alignment

mainline inclusion
from mainline-5.0
commit c3fcadf0
category: bugfix
bugzilla: 11726
CVE: NA

-------------------------------------------------

Define auxtrace record alignment so that it can be referenced elsewhere.

Note this is preparation for patch "perf intel-pt: Fix overlap calculation
for padding"

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20190206103947.15750-2-adrian.hunter@intel.com


Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Wei Li <liwei391@huawei.com>
Reviewed-by: Cheng Jian <cj.chengjian@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>