ByteAddressBuffer support

[damyanp]

• [HLSL] support ByteAdressBuffer llvm-project#58654
• [HLSL] Implement templated ByteAddressBuffer load/store methods llvm-project#108058
• Add tests for ByteAddressBuffer's templated load/store member functions offload-test-suite#266

[hekota]

Closing this as we won't be using umbrella tasks like this going forward.