Puff: Add MKBP driver

Since we don't have 8042 keyboard driver,
depthcharge can't detect power button events from EC w/o MKBP.

BUG=b:148508062
BRANCH=none
TEST=firmware_FwScreenPressPower FAFT passes

Change-Id: Ibd1850f1a0037270f186cee0aa2725442743dca3
Signed-off-by: Kangheui Won <khwon@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/depthcharge/+/2030084
Reviewed-by: Sam McNally <sammc@chromium.org>
Reviewed-by: Edward O'Callaghan <quasisec@chromium.org>
Commit-Queue: Sam McNally <sammc@chromium.org>
diff --git a/board/puff/defconfig b/board/puff/defconfig
index 0847499..355e121 100644
--- a/board/puff/defconfig
+++ b/board/puff/defconfig
@@ -29,6 +29,8 @@
 CONFIG_DRIVER_EC_CROS_LPC=y
 CONFIG_DRIVER_EC_PS8751=y
 CONFIG_DRIVER_FLASH_MEMMAPPED=y
+CONFIG_DRIVER_INPUT_MKBP=y
+CONFIG_DRIVER_INPUT_MKBP_KEYMATRIX_STANDARD=y
 CONFIG_DRIVER_POWER_PCH=y
 CONFIG_DRIVER_SDHCI=y
 CONFIG_DRIVER_SOC_CANNONLAKE=y