Display debug message before shutting down to protect the battery.
Display debug message before shutting down to protect the battery.

The serial console was showing that the CPU was being forcefully shut down,
but I couldn't figure out why. Add a debug message so I'll know next time.

BUG=none
TEST=none
BRANCH=none

Change-Id: I6216711d03fd5e08190b9f0528a4bd8948b74dd8
Signed-off-by: Bill Richardson <129945214b1d548d8e49b6c29c43094f8c78057f@chromium.org>
Reviewed-on: https://gerrit.chromium.org/gerrit/30606
Reviewed-by: Randall Spangler <62698fdbb84d1779579ee80c3f39fac22017e5bc@chromium.org>

longsleep/ec,coreboot/chrome-ec,eatbyte/chromium-ec,mtk09422/chromiumos-platform-ec,akappy7/ChromeOS_EC_LED_Diagnostics,longsleep/ec,fourier49/BZ_DEV_EC,alterapraxisptyltd/chromium-ec,gelraen/cros-ec,coreboot/chrome-ec,alterapraxisptyltd/chromium-ec,fourier49/BZ_DEV_EC,akappy7/ChromeOS_EC_LED_Diagnostics,gelraen/cros-ec,akappy7/ChromeOS_EC_LED_Diagnostics,coreboot/chrome-ec,fourier49/BIZ_EC,akappy7/ChromeOS_EC_LED_Diagnostics,mtk09422/chromiumos-platform-ec,coreboot/chrome-ec,md5555/ec,akappy7/ChromeOS_EC_LED_Diagnostics,thehobn/ec,eatbyte/chromium-ec,thehobn/ec,mtk09422/chromiumos-platform-ec,alterapraxisptyltd/chromium-ec,fourier49/BIZ_EC,thehobn/ec,fourier49/BZ_DEV_EC,fourier49/BZ_DEV_EC,md5555/ec,coreboot/chrome-ec,gelraen/cros-ec,longsleep/ec,thehobn/ec,mtk09422/chromiumos-platform-ec,fourier49/BIZ_EC,md5555/ec,md5555/ec,fourier49/BIZ_EC,longsleep/ec,gelraen/cros-ec,alterapraxisptyltd/chromium-ec,eatbyte/chromium-ec,eatbyte/chromium-ec,coreboot/chrome-ec