x86,fs/resctrl: Prepare for more monitor events

There's a rule in computer programming that objects appear zero, once, or many
times. So code accordingly.

There are two MBM events and resctrl is coded with a lot of

  if (local)
          do one thing
  if (total)
          do a different thing

Change the rdt_mon_domain and rdt_hw_mon_domain structures to hold arrays of
pointers to per event data instead of explicit fields for total and local
bandwidth.

Simplify by coding for many events using loops on which are enabled.

Move resctrl_is_mbm_event() to <linux/resctrl.h> so it can be used more
widely. Also provide a for_each_mbm_event_id() helper macro.

Cleanup variable names in functions touched to consistently use "eventid" for
those with type enum resctrl_event_id.

Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Babu Moger <babu.moger@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Link: https://lore.kernel.org/cover.1757108044.git.babu.moger@amd.com