Disable esimd_pack_unpack_mask test on OpenCL (intel#902)

The test was validated on old version of GPU driver.
Newer version used in CI today exposes an issue with this test.

Author: bader

SYCL/ESIMD/api/esimd_pack_unpack_mask.cpp

@@ -9,6 +9,8 @@
 // UNSUPPORTED: cuda || hip
 // TODO: esimd_emulator fails due to unimplemented 'single_task()' method
 // XFAIL: esimd_emulator
+// TODO: fails on OpenCL - https://github.com/intel/llvm-test-suite/issues/901
+// UNSUPPORTED: opencl
 // RUN: %clangxx -fsycl %s -fsycl-device-code-split=per_kernel -o %t.out
 // RUN: %GPU_RUN_PLACEHOLDER %t.out
 //