Basic CSharp packaging support for ROCm EP

[cloudhan]

This PR mainly fixes building errors when trying to build nupkg for ROCm EP.
It also slighly improve the packaging logic so that devlopers can produce the nupkg on linux natively.

[yuslepukhin]

ORT_API_STATUS(OrtSess

All new APIs must go at the end of the structure to preserve ABI compatibility. They also must be initialized.
Perhaps, this does not belong to this PR

[cloudhan]

This is an old API, it belongs to the global scope, no struct involved, so there is no need for initializing as in OrtApi stuct. I am doubt this decl will affect the ABI tho. The API has already been implemented at

onnxruntime/onnxruntime/core/session/provider_bridge_ort.cc

Lines 1557 to 1562 in 9d26f8f

	ORT_API_STATUS_IMPL(OrtSessionOptionsAppendExecutionProvider_ROCM, _In_ OrtSessionOptions* options, int device_id) {
	OrtROCMProviderOptions provider_options{};
	provider_options.device_id = device_id;
	return OrtApis::SessionOptionsAppendExecutionProvider_ROCM(options, &provider_options);
	}

. This decl just expose it, so the C# dll can use it to initialize a sess with the devcie_id API. Subsequent PR adds API for initializing with provider options.

[yuslepukhin]

[yuslepukhin]