cmake: don't install some test executable

To be equal in what autotools do...

Change-Id: Ib9f1609f803622a364a08e2c73d6c0fae3d85f3f
Signed-off-by: Damjan Marion <damarion@cisco.com>
diff --git a/src/vcl/CMakeLists.txt b/src/vcl/CMakeLists.txt
index 840a62a..b6d4964 100644
--- a/src/vcl/CMakeLists.txt
+++ b/src/vcl/CMakeLists.txt
@@ -50,7 +50,8 @@
     test_vcl_listener_server
     test_vcl_listener_client
   )
-    add_vpp_executable(${test} SOURCES ${test}.c LINK_LIBRARIES vppcom)
+    add_vpp_executable(${test} SOURCES ${test}.c LINK_LIBRARIES vppcom
+		       NO_INSTALL)
   endforeach()
 endif(VPP_BUILD_VCL_TESTS)