libgo: Add mount flags, fallocate, statfs.

From-SVN: r184365
diff --git a/libgo/runtime/go-nosys.c b/libgo/runtime/go-nosys.c
index 6b32854..b282958 100644
--- a/libgo/runtime/go-nosys.c
+++ b/libgo/runtime/go-nosys.c
@@ -48,6 +48,18 @@
 }
 #endif
 
+#ifndef HAVE_FALLOCATE
+int
+fallocate (int fd __attribute__ ((unused)),
+	   int mode __attribute__ ((unused)),
+	   off_t offset __attribute __ ((unused)),
+	   off_t len __attribute__ ((unused)))
+{
+  errno = ENOSYS;
+  return -1;
+}
+#endif
+
 #ifndef HAVE_FCHMODAT
 int
 fchmodat (int dirfd __attribute__ ((unused)),