Disable unused private field for dEQP compilation Incoming VK-GL-CTS rolls are failing due to the following error for some dEQP targets: "private field 'm_size' is not used [-Werror,-Wunused-private-field]" This warning can be suppressed for this target temporarily, allowing the autoroller to merge new changes. Once the issue has been addressed on the CTS code, this change should be reverted. * Added -Wno-unused-private-field to gles2 and gles31 targets. * This is a temporary change. It should be removed once the issue has been addressed. Bug: angleproject:420728429 Change-Id: I0177ded84ad58a148884e8abfac3aea9a1ff7d43 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/6604679 Commit-Queue: Amirali Abdolrashidi <abdolrashidi@google.com> Reviewed-by: Yuxin Hu <yuxinhu@google.com>