cmake CHECK_CURL_HAS_TLS_PROXY examples

aws/aws-sdk-cpp src/aws-cpp-sdk-core/CMakeLists.txt :167 

check_c_source_compiles("${CHECK_CURL_HAS_TLS_PROXY}" CURL_HAS_TLS_PROXY)

aws/aws-sdk-cpp src/aws-cpp-sdk-core/CMakeLists.txt :170 

check_c_source_runs("${CHECK_CURL_HAS_TLS_PROXY}" CURL_HAS_TLS_PROXY)