Fix detecting boot keys on EVT
Fix detecting boot keys on EVT

EVT uses power+refresh as the Silego combination not power+esc, so
holding down power+esc+D wouldn't turn on the fake dev switch, and
holding down power+refresh+D wouldn't either because on a short enough
tap the EC would measure refresh as still held down.

BUG=chrome-os-partner:10210
TEST=manual

1) hold down reset combo + D -> turns on fake dev mode
2) hold down reset combo + F -> turns off fake dev mode

Change-Id: I85b51d3684500ae821513e71a2cd01aa4fcf5e8f
Signed-off-by: Randall Spangler <62698fdbb84d1779579ee80c3f39fac22017e5bc@chromium.org>
Reviewed-on: https://gerrit.chromium.org/gerrit/24646

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