[NaCl SDK] nacl_io: Remove unneeded glibc syscall entry points.

native_client_sdk/src/libraries/nacl_io/kernel_wrap_newlib.cc

Index: native_client_sdk/src/libraries/nacl_io/kernel_wrap_newlib.cc
diff --git a/native_client_sdk/src/libraries/nacl_io/kernel_wrap_newlib.cc b/native_client_sdk/src/libraries/nacl_io/kernel_wrap_newlib.cc
index 1236e5da161f5de0fb75966afded3b66ea1cce70..e992c2784b6fc458991d2607d47a1eed796270e4 100644
--- a/native_client_sdk/src/libraries/nacl_io/kernel_wrap_newlib.cc
+++ b/native_client_sdk/src/libraries/nacl_io/kernel_wrap_newlib.cc
@@ -311,7 +311,8 @@ int _real_lseek(int fd, off_t offset, int whence, off_t* new_offset) {
 }
 
 int _real_mkdir(const char* pathname, mode_t mode) {
-  return ENOSYS;
+  CHECK_REAL(mkdir);
+  return REAL(mkdir)(pathname, mode);
 }
 
 int _real_mmap(void** addr,
@@ -344,7 +345,8 @@ int _real_read(int fd, void* buf, size_t count, size_t* nread) {
 }
 
 int _real_rmdir(const char* pathname) {
-  return ENOSYS;
+  CHECK_REAL(rmdir);
+  return REAL(rmdir)(pathname);
 }
 
 int _real_write(int fd, const void* buf, size_t count, size_t* nwrote) {