[NaCl SDK] Fix getcwd for bionic.

native_client_sdk/src/libraries/nacl_io/kernel_wrap_bionic.cc

Index: native_client_sdk/src/libraries/nacl_io/kernel_wrap_bionic.cc
diff --git a/native_client_sdk/src/libraries/nacl_io/kernel_wrap_bionic.cc b/native_client_sdk/src/libraries/nacl_io/kernel_wrap_bionic.cc
index a72deb5b43a088eb6c7972805f01db9b688b0505..ae2a85dccf330fc3cd8f810dd7a15cb761524479 100644
--- a/native_client_sdk/src/libraries/nacl_io/kernel_wrap_bionic.cc
+++ b/native_client_sdk/src/libraries/nacl_io/kernel_wrap_bionic.cc
@@ -197,7 +197,7 @@ int WRAP(fsync)(int fd) NOTHROW {
   return (ki_fsync(fd)) ? errno : 0;
 }
 
-char* WRAP(getcwd)(char* buf, size_t size) {
+int WRAP(getcwd)(char* buf, size_t size) {
   if (ki_getcwd(buf, size) == NULL)
     return errno;
   return 0;