Export Armnn cmake

Change-Id: I3c317e835aba5feafda240393ca26b6aebe8d655
Signed-off-by: Derek Lamberti <derek.lamberti@arm.com>
diff --git a/cmake/GlobalConfig.cmake b/cmake/GlobalConfig.cmake
index b093e5d..cc44efd 100644
--- a/cmake/GlobalConfig.cmake
+++ b/cmake/GlobalConfig.cmake
@@ -123,6 +123,8 @@
 
 set(CMAKE_MODULE_PATH ${CMAKE_CURRENT_SOURCE_DIR}/cmake/modules ${CMAKE_MODULE_PATH})
 
+include(CMakeFindDependencyMacro)
+
 if (NOT BUILD_PIPE_ONLY)
   # Boost
   message(STATUS "Finding Boost")
@@ -151,7 +153,7 @@
 endif()
 
 # pthread
-find_package (Threads)
+find_dependency(Threads)
 
 # Favour the protobuf passed on command line
 if(BUILD_TF_PARSER OR BUILD_CAFFE_PARSER OR BUILD_ONNX_PARSER)