net: coap_client: Use buffers instead of pointers for path and options

Use buffers instead of pointers for path and extra options provided in
the struct coap_client_request, so that the library keeps a copy of the
path/options instead of pointers. That way, the library can still work
correctly in case of retransmissions or block transfer in case when the
original path or options were automatic variables that went out of
context.

Signed-off-by: Robert Lubos <robert.lubos@nordicsemi.no>
7 files changed