[Bugfix] Fix Windows build, recently added GNUTLS compat code broke it.

git-svn-id: svn://svn.code.sf.net/p/tigervnc/code/trunk@4279 3789f03b-4d11-0410-bbf8-ca57d06f2519
diff --git a/common/os/tls.h b/common/os/tls.h
index 6dd0f32..8980197 100644
--- a/common/os/tls.h
+++ b/common/os/tls.h
@@ -23,7 +23,11 @@
 #include <config.h>
 #endif
 
-#ifdef HAVE_GNUTLS
+/*
+ * Windows builds are build against fairly new GNUTLS, ignore compatibility
+ * code.
+ */
+#if defined(HAVE_GNUTLS) && !defined(WIN32)
 #include <gnutls/gnutls.h>
 
 #ifndef HAVE_GNUTLS_DATUM_T
@@ -40,9 +44,6 @@
 #endif
 
 #ifndef HAVE_GNUTLS_X509_CRT_PRINT
-#ifdef WIN32
-#error "Please install more recent GNUTLS with gnutls_x509_crt_print() function"
-#endif
 
 typedef enum {
 	GNUTLS_CRT_PRINT_ONELINE = 1