cmake: add gnutls to multissl feature

Closes #14345

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 1ea35e70307974bdfb6802b5120a0fbbd6b169f8..990c745b5fc0f865e6b5cca06b3a795a737b9c5a 100644 (file)
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -419,6 +419,7 @@ count_true(enabled_ssl_options_count
   CURL_USE_MBEDTLS
   CURL_USE_BEARSSL
   CURL_USE_WOLFSSL
+  CURL_USE_GNUTLS
 )
 if(enabled_ssl_options_count GREATER "1")
   set(CURL_WITH_MULTI_SSL ON)