Follow the model of how things are done for Contiki.
Set up a new WITH_LWIP_NO_SOCKET (which happens with NO_SYS = 1)
and use this when setting up addresses.
Add in platform specific for dtls_prng_lwip.c and lwip_platform.h
Update dtls_time.[ch] to handle LWIP version of time.
Code works for NO_SYS = 1 or NO_SYS = 0.
Signed-off-by: Jon Shallow <supjps-libcoap@jpshallow.com>
Fixes dtls_config.h not visible in headers
Include dtls_config.h in tinydtls.h and include tinydtls.h in all necessary
headers.
Remaining headers do not use 'ifdef', but they may require it too.
Change-Id: I39c86dffc8bbc8bd7551e74386994f92f49d00ec
Signed-off-by: Gaëtan Harter <gaetan.harter@inria.fr>