Rename SSL_write_early() to SSL_write_early_data()

This is for consistency with the rest of the API where all the functions
are called *early_data*.

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2737)
diff --git a/ssl/ssl_err.c b/ssl/ssl_err.c
index 0a23218..6fe8e6e 100644
--- a/ssl/ssl_err.c
+++ b/ssl/ssl_err.c
@@ -255,7 +255,7 @@
     {ERR_FUNC(SSL_F_SSL_VALIDATE_CT), "ssl_validate_ct"},
     {ERR_FUNC(SSL_F_SSL_VERIFY_CERT_CHAIN), "ssl_verify_cert_chain"},
     {ERR_FUNC(SSL_F_SSL_WRITE), "SSL_write"},
-    {ERR_FUNC(SSL_F_SSL_WRITE_EARLY), "SSL_write_early"},
+    {ERR_FUNC(SSL_F_SSL_WRITE_EARLY_DATA), "SSL_write_early_data"},
     {ERR_FUNC(SSL_F_SSL_WRITE_EARLY_FINISH), "SSL_write_early_finish"},
     {ERR_FUNC(SSL_F_SSL_WRITE_EX), "SSL_write_ex"},
     {ERR_FUNC(SSL_F_SSL_WRITE_INTERNAL), "ssl_write_internal"},