[PATCH] shpchp: Remove Unused hpc_evelnt_lock

This patch removes unused hpc_event_lock. This patch has no functional
change.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Cc: Kristen Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>