Ensure syscall functions are consistently prefixed with "NaClSys"

src/untrusted/irt/irt_memory.c

 /*
  * Copyright (c) 2011 The Native Client Authors. All rights reserved.
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include <errno.h>
 #include <stdint.h>
 
 #include "native_client/src/untrusted/irt/irt.h"
 #include "native_client/src/untrusted/nacl/syscall_bindings_trampoline.h"
 
 static int nacl_irt_sysbrk(void **newbrk) {
   /*
    * The syscall does not actually indicate error.  It just returns the
    * new current value, which is unchanged if something went wrong.
    * But if the requested value was below the end of the data segment,
    * the new value will be greater, but this is not "going wrong".
    * Here we just approximate a saner interface: you get what you requested,
    * you did a "probe" request passing NULL in, or it's an error.
    * TODO(mcgrathr): this interface should just go away!!
    */
   void *requested = *newbrk;
-  void *got = NACL_SYSCALL(sysbrk)(requested);
+  void *got = NACL_SYSCALL(brk)(requested);
 
   if (got == requested || requested == NULL) {
     *newbrk = got;
     return 0;
   }
 
   return ENOMEM;
 }
 
 static int nacl_irt_mmap(void **addr, size_t len,
                          int prot, int flags, int fd, off_t off) {
   uint32_t rv = (uintptr_t) NACL_SYSCALL(mmap)(*addr, len, prot, flags,
                                                fd, &off);
   if ((uint32_t) rv > 0xffff0000u)
     return -(int32_t) rv;
   *addr = (void *) (uintptr_t) rv;
   return 0;
 }
 
 static int nacl_irt_munmap(void *addr, size_t len) {
   return -NACL_SYSCALL(munmap)(addr, len);
 }
 
 const struct nacl_irt_memory nacl_irt_memory = {
   nacl_irt_sysbrk,
   nacl_irt_mmap,
   nacl_irt_munmap,
 };