Split UMF_RESULT_ERROR_OUT_OF_HOST_MEMORY into Distinct Error Codes

[lplewa]

Description:

Currently, the umf_result_t enumeration includes an error code UMF_RESULT_ERROR_OUT_OF_HOST_MEMORY that is used in two distinct scenarios within the UMF library:

1. When the UMF library fails to allocate host memory for its internal metadata structures.
2. When a memory provider fails to allocate memory because it has exhausted its available memory resources.

Using the same error code for both situations can make it difficult for developers to accurately diagnose and handle errors, as the root causes might be different (especially for providers like: gpu, dax etc...).

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Proposal:

Split UMF_RESULT_ERROR_OUT_OF_HOST_MEMORY into two separate error codes:

1. UMF_RESULT_ERROR_OUT_OF_HOST_MEMORY: Retain this error code to exclusively represent failures in allocating host memory for UMF's internal metadata and operations.

2. UMF_RESULT_ERROR_MEMORY_PROVIDER_OUT_OF_MEMORY: Introduce this new error code to indicate that a memory provider has run out of memory and cannot fulfill the allocation request.

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