eap-radius: Don't include socket.h explicitly

We rely on the includes via utils.h so this compiles on Windows.

src/libcharon/plugins/eap_radius/eap_radius_dae.c

@@ -18,9 +18,6 @@
 
 #include <radius_message.h>
 
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <sys/socket.h>
 #include <unistd.h>
 #include <errno.h>