use restrict everywhere it's required by c99 and/or posix 2008

to deal with the fact that the public headers may be used with pre-c99
compilers, __restrict is used in place of restrict, and defined
appropriately for any supported compiler. we also avoid the form
[restrict] since older versions of gcc rejected it due to a bug in the
original c99 standard, and instead use the form *restrict.

include/aio.h

@@ -5,6 +5,12 @@
 extern "C" {
 #endif
 
+#if __STDC_VERSION__ >= 199901L
+#define __restrict restrict
+#elif !defined(__GNUC__)
+#define __restrict
+#endif
+
 #include <signal.h>
 #include <time.h>
 
@@ -46,7 +52,7 @@ int aio_cancel(int, struct aiocb *);
 int aio_suspend(const struct aiocb *const [], int, const struct timespec *);
 int aio_fsync(int, struct aiocb *);
 
-int lio_listio(int, struct aiocb *const [], int, struct sigevent *);
+int lio_listio(int, struct aiocb *__restrict const *__restrict, int, struct sigevent *__restrict);
 
 #if defined(_LARGEFILE64_SOURCE) || defined(_GNU_SOURCE)
 #define aiocb64 aiocb