When we receive CoAP packets, it is in input buffer
that is size of NET_IPV6_MTU.
So in reality, we can handle bigger Block-Wise writes
than CONFIG_LWM2M_COAP_BLOCK_SIZE.
So if parsing of CoAP packet has passed, continue
with the same block-size instead of going to default.
Signed-off-by: Seppo Takalo <seppo.takalo@nordicsemi.no>
d3081e2f30