driver: wifi: simplelink: Fix socket offload after s_addr cleanup

The commit 8592501
("net: Remove s_addr/s6_addr defines from in_addr/in6_addr")

did a (welcomed) removal of a #define s_addr for which the SimpleLink
SDK was checking, breaking the socket_offload driver build.

This patch fixes the driver to work with this new, better
s_addr symbol definition.

Signed-off-by: Gil Pitney <gil.pitney@linaro.org>

drivers/wifi/simplelink/simplelink_sockets.c

@@ -76,7 +76,7 @@ static SlSockAddr_t *translate_z_to_sl_addrs(const struct sockaddr *addr,
 		*sl_addrlen = sizeof(SlSockAddrIn_t);
 		sl_addr_in->sin_family = AF_INET;
 		sl_addr_in->sin_port = z_sockaddr_in->sin_port;
-		sl_addr_in->sin_addr.S_un.S_addr =
+		sl_addr_in->sin_addr.s_addr =
 			z_sockaddr_in->sin_addr.s_addr;
 
 		sl_addr = (SlSockAddr_t *)sl_addr_in;
@@ -114,7 +114,7 @@ static void translate_sl_to_z_addr(SlSockAddr_t *sl_addr,
 			z_sockaddr_in->sin_family = AF_INET;
 			z_sockaddr_in->sin_port = sl_addr_in->sin_port;
 			z_sockaddr_in->sin_addr.s_addr =
-				sl_addr_in->sin_addr.S_un.S_addr;
+				sl_addr_in->sin_addr.s_addr;
 			*addrlen = sizeof(struct sockaddr_in);
 		} else {
 			*addrlen = sl_addrlen;