Remove it, it's the same as the generic one in ../common

libc/sysdeps/linux/vax/vfork.c

@@ -1,14 +0,0 @@
-#include <errno.h>
-#include <features.h>
-#include <sys/types.h>
-#include <sys/syscall.h>
-#include <unistd.h>
-
-libc_hidden_proto(vfork)
-pid_t
-vfork (void)
-{
-	return __fork ();
-}
-libc_hidden_def(vfork)
-