[linux] Const sigar_meminfo and sigar_vmstat
[linux] Const sigar_meminfo and sigar_vmstat

Change-Id: I4018587b2f317f305d9ca16430ffd456f9fb02c6
Reviewed-on: https://review.couchbase.org/c/sigar/+/167059
Tested-by: Build Bot <80754af91bfb6d1073585b046fe0a474ce868509@couchbase.com>
Reviewed-by: Dave Rigby <a09264da4832c7ff1d3bf1608a19f4b870f93750@couchbase.com>

couchbase/sigar,couchbase/sigar