perf lock contention: Fix typo in max-stack option description

Fix typo in max-stack option description by changing lopck contention
to lock contention.

Signed-off-by: Kajol Jain <kjain@linux.ibm.com>
Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: Disha Goel <disgoel@linux.ibm.com>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20230825104700.440809-1-kjain@linux.ibm.com


Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>