Align the first member of `struct sockaddr` and
`struct sockaddr_storage` as `uint32_t` to elevate the alignment of the
structure to level of `uint32_t`. This is needed as
`struct sockaddr_in` uses an `uint32_t` to store the IPv4 address,
previously resulting in `struct sockaddr_in` currently having a greater
alignment requirement that `struct sockaddr_storage`.
AwaLWM2M needs to be polled regularly to check for incoming data.
Since RIOT only supports timeout at the GNRC sock layer while
the network abstraction for RIOT in AwaLWM2M uses the posix layer,
this causes RIOT to be blocked waiting for data that never arrive.
This commit implements only the SO_RCVTIMEO option in setsockopt to
allow users to set a receive timeout for a socket at the posix layer.
Signed-off-by: Francois Berder <francois.berder@imgtec.com>
