Add an example of the DevDax memory provider with the jemalloc pool and the disable_provider_free parameter set to true

[ldorau]

Add an example of the DevDax memory provider with the jemalloc pool and the disable_provider_free parameter set to true.

Rationale

The DevDax memory provider does not support the free operation
(umfMemoryProviderFree() always returns UMF_RESULT_ERROR_NOT_SUPPORTED),
so it should be used with a pool manager that will take over
the managing of the provided memory - for example the jemalloc pool
with the disable_provider_free parameter set to true.

Ref: #671 (comment)

Description

Add an example of the DevDax memory provider with the jemalloc pool and the disable_provider_free parameter set to true.