[LIBCLC] Extend __CLC_NVVM_ATOMIC with generic AS

[jchlanda]

The diffs don't show it very well, but this patch extends __CLC_NVVM_ATOMIC macro to generate one more overload, targetting a generic address space, while at it, it also fixes a mangled name used in the implementation of __CLC_NVVM_ATOMIC_IMPL_SUBSTITUTION.

[jchlanda]

Fixes: #6505

[steffenlarsen]

LGTM!

[bader]

@jchlanda, please, remove XFAIL mark for cuda in llvm-test-suite tests.

Unexpectedly Passed Tests (16):
  SYCL :: AtomicRef/add_generic.cpp
  SYCL :: AtomicRef/add_generic_local.cpp
  SYCL :: AtomicRef/add_generic_local_native_fp.cpp
  SYCL :: AtomicRef/add_generic_native_fp.cpp
  SYCL :: AtomicRef/and_generic.cpp
  SYCL :: AtomicRef/and_generic_local.cpp
  SYCL :: AtomicRef/exchange_generic.cpp
  SYCL :: AtomicRef/exchange_generic_local.cpp
  SYCL :: AtomicRef/or_generic.cpp
  SYCL :: AtomicRef/or_generic_local.cpp
  SYCL :: AtomicRef/sub_generic.cpp
  SYCL :: AtomicRef/sub_generic_local.cpp
  SYCL :: AtomicRef/sub_generic_local_native_fp.cpp
  SYCL :: AtomicRef/sub_generic_native_fp.cpp
  SYCL :: AtomicRef/xor_generic.cpp
  SYCL :: AtomicRef/xor_generic_local.cpp

[jchlanda]

/verify with intel/llvm-test-suite#1382

[jchlanda]

@jchlanda, please, remove XFAIL mark for cuda in llvm-test-suite tests.

Unexpectedly Passed Tests (16):
  SYCL :: AtomicRef/add_generic.cpp
  SYCL :: AtomicRef/add_generic_local.cpp
  SYCL :: AtomicRef/add_generic_local_native_fp.cpp
  SYCL :: AtomicRef/add_generic_native_fp.cpp
  SYCL :: AtomicRef/and_generic.cpp
  SYCL :: AtomicRef/and_generic_local.cpp
  SYCL :: AtomicRef/exchange_generic.cpp
  SYCL :: AtomicRef/exchange_generic_local.cpp
  SYCL :: AtomicRef/or_generic.cpp
  SYCL :: AtomicRef/or_generic_local.cpp
  SYCL :: AtomicRef/sub_generic.cpp
  SYCL :: AtomicRef/sub_generic_local.cpp
  SYCL :: AtomicRef/sub_generic_local_native_fp.cpp
  SYCL :: AtomicRef/sub_generic_native_fp.cpp
  SYCL :: AtomicRef/xor_generic.cpp
  SYCL :: AtomicRef/xor_generic_local.cpp

Done in: intel/llvm-test-suite#1382

[jchlanda]

/verify with intel/llvm-test-suite#1382

[steffenlarsen]

Failure on Windows for KernelAndProgram/kernel-bundle-merge-options-env.cpp is known and is unrelated.