Unconditionally include SYCL standard header and drop compatibilty guards for earlier versions that do not meet our new minimum toolchain requirements.
* Drop OpenMPTarget "category" test header file * Drop Dockerfile dedicated to OpenMPTarget testing/development * Remove stray guards for OpenMPTarget in tests * Purge OpenMPTarget from core tests CMakeLists.txt * Purge OpenMPTarget from SIMD * Purge OpenMPTarget from core performance tests * Sweep core source for OpenMPTarget * Remove OpenMPTarget special casing in atomic operation tests * Cleanup more core tests * Another batch of ompt cleanup in core tests * Remove OpenMPTarget skips from unit tests.
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Signed-off-by: Damien L-G <dalg24@gmail.com> Signed-off-by: Christian Trott <crtrott@sandia.gov> Co-authored-by: Rahulkumar Gayatri <rgayatri@lbl.gov> Co-authored-by: Christian Trott <crtrott@sandia.gov> Co-authored-by: Daniel Arndt <arndtd@ornl.gov> (commit: 3010e46)