cc-wrapper: Use MacOS compatible mktemp command

The commit 6f2b3ba027f0d74614ba1b21f15ea45b0beb0385 introduced a
`mktemp` invokation that uses the `--tmpdir` flag, which is not
available on MacOS.

This changes the invokation to a portable one based on the following
StackOverflow answer https://stackoverflow.com/a/31397073/841562 .

pkgs/build-support/cc-wrapper/cc-wrapper.sh

···
 fi
 
 if (( "${NIX_CC_USE_RESPONSE_FILE:-@use_response_file_by_default@}" >= 1 )); then
-    responseFile=$(mktemp --tmpdir cc-params.XXXXXX)
+    responseFile=$(mktemp "${TMPDIR:-/tmp}/cc-params.XXXXXX")
     trap 'rm -f -- "$responseFile"' EXIT
     printf "%q\n" \
        ${extraBefore+"${extraBefore[@]}"} \