Cygwin: cleanup header including within network-releated files

* Rearrange includes and drop unneccessary ones.

* Don't pull in cygwin/socket.h into sys/un.h just to get
  sa_family_t.  Include sys/types.h and use __sa_family_t instead.

* start including Windows headers using the w32api/ path prefix

Signed-off-by: Corinna Vinschen <corinna@vinschen.de>

winsup/cygwin/fhandler_socket_local.cc

@@ -21,31 +21,23 @@
 #undef u_long
 #define u_long __ms_u_long
 #endif
-#include <ntsecapi.h>
-#include <ws2tcpip.h>
-#include <mswsock.h>
-#include <iphlpapi.h>
+#include <w32api/ntsecapi.h>
+#include <w32api/ws2tcpip.h>
+#include <w32api/mswsock.h>
+#include <unistd.h>
+#include <asm/byteorder.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <sys/param.h>
+#include <sys/statvfs.h>
+#include <cygwin/acl.h>
 #include "cygerrno.h"
-#include "security.h"
 #include "path.h"
 #include "fhandler.h"
 #include "dtable.h"
 #include "cygheap.h"
-#include <asm/byteorder.h>
-#include "cygwin/version.h"
-#include "perprocess.h"
-#include "shared_info.h"
-#include "sigproc.h"
 #include "wininfo.h"
-#include <unistd.h>
-#include <sys/param.h>
-#include <sys/statvfs.h>
-#include <cygwin/acl.h>
-#include "cygtls.h"
-#include <sys/un.h>
 #include "ntdll.h"
-#include "miscfuncs.h"
-#include "tls_pbuf.h"
 
 extern "C" {
   int sscanf (const char *, const char *, ...);