readdir_r is deprecated

[Piratonym]

GNU libc 2.24 (published 2016-08-04) deprecated readdir_r, see the announcement email:

• The readdir_r and readdir64_r functions have been deprecated. It is
  recommended to use readdir and readdir64 instead.

This causes the build to fail:

[566/727] Building C object boringssl/decrepit/ssl/CMakeFiles/ssl_decrepit.dir/ssl_decrepit.c.o
FAILED: boringssl/decrepit/ssl/CMakeFiles/ssl_decrepit.dir/ssl_decrepit.c.o 
/usr/bin/cc  -DBORINGSSL_IMPLEMENTATION -DUSE_OPENSSL -D__STDC_CONSTANT_MACROS -D__STDC_LIMIT_MACROS -I../src -I../src/third_party/modp_b64 -I../boringssl/include -I../src/third_party/protobuf/src -I/src -I../boringssl/decrepit/ssl/../../include -Wall -fpic -gdwarf-4 -Wall -Werror -Wformat=2 -Wsign-compare -Wmissing-field-initializers -ggdb -fvisibility=hidden -Wmissing-prototypes -Wshadow -std=c11 -D_XOPEN_SOURCE=700 -g -MD -MT boringssl/decrepit/ssl/CMakeFiles/ssl_decrepit.dir/ssl_decrepit.c.o -MF boringssl/decrepit/ssl/CMakeFiles/ssl_decrepit.dir/ssl_decrepit.c.o.d -o boringssl/decrepit/ssl/CMakeFiles/ssl_decrepit.dir/ssl_decrepit.c.o   -c ../boringssl/decrepit/ssl/ssl_decrepit.c
../boringssl/decrepit/ssl/ssl_decrepit.c: In function ‘OPENSSL_DIR_read’:
../boringssl/decrepit/ssl/ssl_decrepit.c:157:3: error: ‘readdir_r’ is deprecated [-Werror=deprecated-declarations]
   if (readdir_r((*ctx)->dir, &(*ctx)->dirent, &dirent) != 0 ||
   ^~
In file included from ../boringssl/decrepit/ssl/ssl_decrepit.c:115:0:
/usr/include/dirent.h:183:12: note: declared here
 extern int readdir_r (DIR *__restrict __dirp,
            ^~~~~~~~~
cc1: all warnings being treated as errors
[…]
ninja: build stopped: subcommand failed.

[bkfox]

I've tried compiling with git version of boringssl (Change-Id: I4b586dce37f4db0770e516888c2eeeae3ecffd97):

mv boringssl boringssl_
git clone https://github.com/google/boringssl.git

Code needs to be patched:

diff --git a/src/net/quic/core/crypto/chacha20_poly1305_decrypter.cc b/src/net/quic/core/crypto/chacha20_poly1305_decrypter.cc
index 302d105..5ada475 100644
--- a/src/net/quic/core/crypto/chacha20_poly1305_decrypter.cc
+++ b/src/net/quic/core/crypto/chacha20_poly1305_decrypter.cc
@@ -29,11 +29,11 @@ ChaCha20Poly1305Decrypter::ChaCha20Poly1305Decrypter()
 ChaCha20Poly1305Decrypter::~ChaCha20Poly1305Decrypter() {}
 
 const char* ChaCha20Poly1305Decrypter::cipher_name() const {
-  return TLS1_TXT_ECDHE_RSA_WITH_CHACHA20_POLY1305;
+  return TLS1_TXT_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256;
 }
 
 uint32_t ChaCha20Poly1305Decrypter::cipher_id() const {
-  return TLS1_CK_ECDHE_RSA_CHACHA20_POLY1305;
+  return TLS1_CK_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256;
 }
 
 }  // namespace net