unix: skip ncurses host build on macOS

This isn't needed on macOS because the OS tic should be modern
enough. This also is failing in CI (and likely locally as well).

Author: indygreg

cpython-unix/build-ncurses.sh

@@ -16,7 +16,7 @@ tar -xf ncurses-${NCURSES_VERSION}.tar.gz
 # ncurses version. Our workaround is to build ncurses for the host when
 # cross-compiling then make its `tic` available to the target ncurses
 # build.
-if [ "${BUILD_TRIPLE}" != "${TARGET_TRIPLE}" ]; then
+if [[ "${BUILD_TRIPLE}" != "${TARGET_TRIPLE}" && "${PYBUILD_PLATFORM}" != "macos" ]]; then
   echo "building host ncurses to provide modern tic for cross-compile"
 
   pushd ncurses-${NCURSES_VERSION}