lynxpoint: Fix ELOG logging of power management events

This is updated to handle LynxPoint-H and LynxPoint-LP
and a new wake event is added for the power button.

Boot, suspend/resume, reboot, etc on WTM2
and then check the event log to see if expected events
have been added.

Change-Id: I15cbc3901d81f4fd77cc04de37ff5fa048f9d3e8
Signed-off-by: Duncan Laurie <dlaurie@chromium.org>
Reviewed-on: http://review.coreboot.org/2817
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>

src/include/elog.h

@@ -113,6 +113,7 @@
 #define  ELOG_WAKE_SOURCE_RTC              0x03
 #define  ELOG_WAKE_SOURCE_GPIO             0x04
 #define  ELOG_WAKE_SOURCE_SMBUS            0x05
+#define  ELOG_WAKE_SOURCE_PWRBTN           0x06
 struct elog_event_data_wake {
 	u8 source;
 	u32 instance;