spi_transaction() always returns success even without the sensor.
Check whoami value to make sure that the sensor is existed.
BUG=none
BRANCH=none
TEST=remove LID accel sensor from elm and see init failed log.
[1.258973 Lid Accel: 1: init failed: 4]
Change-Id: I55aa35bc9790e5dec61e22aa2f51243e29368a86
Signed-off-by: Yidi Lin <yidi.lin@mediatek.com>
Reviewed-on: https://chromium-review.googlesource.com/453579
Reviewed-by: Gwendal Grignou <gwendal@chromium.org>