Simplesmente rm *.html *.xml
Veja também as man pages do Linux (ou macOS ) ou tente tldr que atualmente fornece este resultado:
$ tldr rm
rm
Remove files or directories.
- Remove files from arbitrary locations:
rm path/to/file path/to/another/file
- Recursively remove a directory and all its subdirectories:
rm -r path/to/folder
- Forcibly remove a directory, without prompting for confirmation or showing error messages:
rm -rf path/to/folder
- Interactively remove multiple files, with a prompt before every removal:
rm -i file(s)
- Remove files in verbose mode, printing a message for each removed file:
rm -v path/to/folder/*
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