- Fix test-security-check fail in Ubuntu 18.04. Those flags are enabled
by default, so we must specify -no to make the executable does 'not'
have those attributes.
 - Drop HIGH_ENTROPY_VA. After update our gitian system to Bionic, the
compiler should support HIGH_ENTROPY_VA

cd contrib/devtools
./test-security-check.py

cmake -GNinja .. \
  -DCMAKE_TOOLCHAIN_FILE=../cmake/platforms/Win32.cmake
  -DBUILD_BITCOIN_SEEDER=OFF
ninja security-check

cmake -GNinja .. \
  -DCMAKE_TOOLCHAIN_FILE=../cmake/platforms/Win64.cmake
  -DBUILD_BITCOIN_SEEDER=OFF
ninja security-check