VMX: sync VM-exit perf counters with known VM-exit reasons

VMX: sync VM-exit perf counters with known VM-exit reasons

This has gone out of sync over time. Introduce a simplistic mechanism to
hopefully keep things in sync going forward.

Also limit the array index to just the "basic exit reason" part, which is
what the pseudo-enumeration covers.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>