The file name under pre-install.d should be like "^[0-9A-Za-z_-]+$",
otherwise the script will be skipped by the name check step and raise
"Ignoring non-conforming filenames" warning.
This patch rename the openeuler mirror script to ensure it follows
the regex.
Change-Id: I6d868df7932345547711100519523546bd53360e
