add missing arg for Foundation prefix

Author: zbowling

utils/build-script-impl

@@ -1804,7 +1804,8 @@ function set_swiftpm_bootstrap_command() {
         --build="${build_dir}")
     if [[ ! "${SKIP_BUILD_FOUNDATION}" ]] ; then
         swiftpm_bootstrap_command+=(
-            --foundation="${FOUNDATION_BUILD_DIR}/Foundation")
+            --foundation="${FOUNDATION_BUILD_DIR}/Foundation"
+            --foundation-install-prefix="$(get_host_install_prefix ${host})")
         if [[ ! "${SKIP_BUILD_LIBDISPATCH}" ]] ; then
             swiftpm_bootstrap_command+=(
                 $LIBDISPATCH_BUILD_ARGS)
@@ -2467,7 +2468,7 @@ for host in "${ALL_HOSTS[@]}"; do
                 ;;
             swiftpm)
                 set_swiftpm_bootstrap_command
-                call "${swiftpm_bootstrap_command[@]}"
+                call "${swiftpm_bootstrap_command[@]}" \
 
                 # swiftpm installs itself with a bootstrap method. No further cmake building is performed.
                 continue
@@ -2494,6 +2495,7 @@ for host in "${ALL_HOSTS[@]}"; do
                     --swiftc="${SWIFTC_BIN}" \
                     --build-dir="${XCTEST_BUILD_DIR}" \
                     --foundation-build-dir="${FOUNDATION_BUILD_DIR}/Foundation" \
+                    --foundation-install-prefix="$(get_host_install_prefix ${host})" \
                     $LIBDISPATCH_BUILD_ARGS \
                     $XCTEST_BUILD_ARGS
 
@@ -2957,6 +2959,7 @@ for host in "${ALL_HOSTS[@]}"; do
                 call "${XCTEST_SOURCE_DIR}"/build_script.py test \
                     --swiftc="${SWIFTC_BIN}" \
                     --foundation-build-dir="${FOUNDATION_BUILD_DIR}/Foundation" \
+                    --foundation-install-prefix="$(get_host_install_prefix ${host})" \
                     ${LIBDISPATCH_BUILD_ARGS} \
                     $XCTEST_BUILD_ARGS \
                     "${XCTEST_BUILD_DIR}"