These tests are currently failing and their fix is being tracked in
Issue #60133. Marking them as XFAIL for now will get the test suite to a
passing state so we can work on adding a GitHub action to automatically
run these tests on a PR bot to help keep the tree green.
Also removed the no-longer supported -opaque-pointers=0 flag from the
couple tests where it was remaining.
The patch adds support of the enqueue_kernel builtin function.
It is implemented in the same way as in the SPIRV translator.
2 LIT tests are added to show the improvement.
Differential Revision: https://reviews.llvm.org/D137018
