Fix compilation with no-compression OpenSSL builds and forks

Found because LibreSSL has OPENSSL_NO_COMP always-on, but this
conflicts with the way that _we_ turn off compression.  Patch from
dhill, who attributes it to "OpenBSD".  Fixes bug 12602; bugfix on
0.2.1.1-alpha, which introduced this turn-compression-off code.

changes/bug12602

@@ -0,0 +1,5 @@
+  o Minor bugfixes (portability):
+    - Compile correctly with builds and forks of OpenSSL (such as
+      LibreSSL) that disable compression. Fixes bug 12602; bugfix on
+      0.2.1.1-alpha. Patch from "dhill".
+

src/common/tortls.c

@@ -1345,10 +1345,12 @@ tor_tls_context_new(crypto_pk_t *identity, unsigned int key_lifetime,
     SSL_CTX_set_options(result->ctx,
                         SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION);
   }
+#ifndef OPENSSL_NO_COMP
   /* Don't actually allow compression; it uses ram and time, but the data
    * we transmit is all encrypted anyway. */
   if (result->ctx->comp_methods)
     result->ctx->comp_methods = NULL;
+#endif
 #ifdef SSL_MODE_RELEASE_BUFFERS
   SSL_CTX_set_mode(result->ctx, SSL_MODE_RELEASE_BUFFERS);
 #endif