ALS: OPT3001: Return appropriate error value
ALS: OPT3001: Return appropriate error value

Return appropriate error value for I2C errors and data verification
errors.

BUG=chrome-os-partner:57512
BRANCH=none
TEST=Manually tested on Reef, ALS data changes when surrounding
     brightness is changed.

Change-Id: I17b5bd10da5fa5cc82fdff10337ae893146c70ee
Signed-off-by: Vijay Hiremath <006c712879a3af08bfdb5c2b8491a8b2d5fd73cd@intel.com>
Reviewed-on: https://chromium-review.googlesource.com/386397
Commit-Ready: Vijay P Hiremath <006c712879a3af08bfdb5c2b8491a8b2d5fd73cd@intel.com>
Commit-Ready: Kevin K Wong <8bf1d1ccd36a6bfde85ceaaa1fe52f2093ecf3aa@intel.com>
Tested-by: Vijay P Hiremath <006c712879a3af08bfdb5c2b8491a8b2d5fd73cd@intel.com>
Reviewed-by: Kevin K Wong <8bf1d1ccd36a6bfde85ceaaa1fe52f2093ecf3aa@intel.com>
Reviewed-by: Shawn N <5259333ce42e3ace6a73988cec7115ed9d3a661a@chromium.org>

coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec