Also, handle ownership transfer for the second device when the
first device is already connected to the hub. Extend the cloud
server to accommodate multiple servers and enhance the check for
empty endpoints.

Check if the iotivity-lite stack is initialized before processing new requests during shutdown.

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Co-authored-by: Daniel Adam <daniel.adam1922@protonmail.com>

Create an oc_string64_t struct with statically allocated buffer that fits an endpoint
address to avoid the use of the heap.
The new function oc_endpoint_to_string64 converts an oc_endpoint_t to a string
address using the oc_string64_t.

Currently used internally.
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Co-authored-by: Daniel Adam <daniel.adam1922@protonmail.com>

Extend the function signature to include the include the length
of the key. If the length of the key is known then a call to
strlen can be avoided.

Added:
  - oc_iterate_query_get_values_v1
  - oc_get_query_value_v1
  - oc_query_value_exists_v1
  - oc_ri_get_query_value_v1
  - oc_ri_query_exists_v1

Deprecated:
  - oc_iterate_query_get_values
  - oc_get_query_value
  - oc_query_value_exists
  - oc_ri_get_query_value
  - oc_ri_query_exists

When a session has been closed, we also need to clean up the process
events associated with the endpoint.

When OC_DYNAMIC_ALLOCATION is disabled then memory allocation by
oc_memb pool from multiple threads needs to be synchronized. For
this purpose oc_allocator_mutex should be used to avoid misusing
other mutexes for this purpose.

Fix compilation on supported Android environments.