Replace ssl3_get_message() with tls_get_message_header() and/or tls_get_message_body()

Update commit messages that previously used ssl3_get_message()
to now use tls_get_message_header() and tls_get_message_body()
due to the split in OpenSSL 1.1.0.

CLA: trivial

Fixes #21582

Signed-off-by: Sumitra Sharma <sumitraartsy@gmail.com>

Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Tom Cosgrove <tom.cosgrove@arm.com>
Reviewed-by: Hugo Landau <hlandau@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/21886)

ssl/record/rec_layer_d1.c

@@ -170,7 +170,7 @@ static void dtls_unbuffer_record(SSL_CONNECTION *s)
  * Return up to 'len' payload bytes received in 'type' records.
  * 'type' is one of the following:
  *
- *   -  SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
+ *   -  SSL3_RT_HANDSHAKE
  *   -  SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
  *   -  0 (during a shutdown, no data has to be returned)
  *

ssl/record/rec_layer_s3.c

@@ -533,7 +533,8 @@ int ssl_release_record(SSL_CONNECTION *s, TLS_RECORD *rr, size_t length)
  * Return up to 'len' payload bytes received in 'type' records.
  * 'type' is one of the following:
  *
- *   -  SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
+ *   -  SSL3_RT_HANDSHAKE (when tls_get_message_header and tls_get_message_body
+ *			   call us)
  *   -  SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
  *   -  0 (during a shutdown, no data has to be returned)
  *

ssl/ssl_local.h

@@ -1258,7 +1258,7 @@ struct ssl_connection_st {
     SSL_EARLY_DATA_STATE early_data_state;
     BUF_MEM *init_buf;          /* buffer used during init */
     void *init_msg;             /* pointer to handshake message body, set by
-                                 * ssl3_get_message() */
+                                 * tls_get_message_header() */
     size_t init_num;               /* amount read/written */
     size_t init_off;               /* amount read/written */