file(MAKE_DIRECTORY): Do not make directories for command keywords

In commit 95323c90a1 (file(MAKE_DIRECTORY): Add optional RESULT keyword
to capture failure., 2024-06-16, v3.31.0-rc1~414^2) we computed an
updated range of arguments, that name directories to be created, before
the `RESULT` keyword.  However, we forgot to use it in the loop.

Fixes: #26768