Deprecate undocumented SSL_cache_hit().

Deprecate undocumented SSL_cache_hit(). Make SSL_session_reused() into a
real function.

Reviewed-by: Richard Levitte <levitte@openssl.org>

ssl/s3_lib.c

@@ -3455,9 +3455,6 @@ long ssl3_ctrl(SSL *s, int cmd, long larg, void *parg)
     int ret = 0;
 
     switch (cmd) {
-    case SSL_CTRL_GET_SESSION_REUSED:
-        ret = s->hit;
-        break;
     case SSL_CTRL_GET_CLIENT_CERT_REQUEST:
         break;
     case SSL_CTRL_GET_NUM_RENEGOTIATIONS:

ssl/ssl_lib.c

@@ -3706,7 +3706,7 @@ int ssl_handshake_hash(SSL *s, unsigned char *out, int outlen)
     return ret;
 }
 
-int SSL_cache_hit(SSL *s)
+int SSL_session_reused(SSL *s)
 {
     return s->hit;
 }