Removed redundant OpenCL ICD library, using regular OpenCL library
instead.

Bug: angleproject:5908
Change-Id: I1ecf5347557106511aed3c5c4a4bfa35590a559a
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2877240Reviewed-by: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Cody Northrop <cnorthrop@google.com>
Commit-Queue: John Plate <jplate@google.com>