poppy: Enable MKBP keyboard protocol
This is used for passing button information from EC to AP.
BRANCH=None
TEST=Verified using evtest that kernel is able to see button
press/release information.
/* TODO(crosbug.com/p/61098): Is this the correct thermistor? */
#define CONFIG_THERMISTOR_NCP15WB
+#define CONFIG_KEYBOARD_PROTOCOL_MKBP
#define CONFIG_MKBP_EVENT
#define CONFIG_MKBP_USE_HOST_EVENT
#define CONFIG_ACCELGYRO_BMI160
