Log event for abnormal management engine status

This will log if the ME is disabled or has an error.

1) disable ME via EC console: gpioset PCH_HDA_SDO 1
2) boot the device
3) read eventlog with "mosys eventlog list"
71 | 2012-07-13 10:10:55 | Management Engine | Disabled

Change-Id: I9f6ee452d2aea76e6a5ea2cd50a50ff36245692a
Signed-off-by: Duncan Laurie <dlaurie@chromium.org>
Reviewed-on: http://review.coreboot.org/1345
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>

src/include/elog.h

@@ -105,6 +105,9 @@ struct elog_event_data_wake {
 #define ELOG_TYPE_CROS_DEVELOPER_MODE     0xa0
 #define ELOG_TYPE_CROS_RECOVERY_MODE      0xa1
 
+/* Management Engine Events */
+#define ELOG_TYPE_MANAGEMENT_ENGINE       0xa2
+
 extern int elog_init(void);
 extern int elog_clear(void);
 extern void elog_add_event_raw(u8 event_type, void *data, u8 data_size);