perf sort: Replace static cacheline size with sysconf cacheline size

perf sort: Replace static cacheline size with sysconf cacheline size

Testing:
- Built perf
- Executed perf mem record and report

Committer notes:

This addresses a TODO and improves the situation where record and
report/c2c are performed on the same machine or in machines with the
same cacheline size, but the proper way is to store the cacheline size
in the perf.data header at 'record' time and then use it at post
processing time.

Signed-off-by: Ricky Ringler <ricky.ringler@proton.me>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20260129004223.26799-1-ricky.ringler@proton.me
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>