XSD Validate - name attributes must not have whitespace

[hamishwillee]

Name attributes must not contain whitespace - that's required because they are used as ids for generated items.

This adds XSD validation to ensure that only word characters are used in name attributes or the _ character.

Note that the pattern check of "\w+" should have been fine because my understanding is that in normal RE this includes the underscore. However running the validator failed on underscores so I was forced to explicitly support them: "[\w_]+"

@peterbarker This follows on from mavlink/mavlink#1824.

Note:

• leading and trailing whitespace would actually be OK, because you could reasonably strip this in the parser. This does not allow it though, and it is never "needed".
• I think the parser should also strip leading/trailing spaces.
• running this on all.xml spots two more fails in AVSSUAS.xml : MODE_M300_HOTPOINT_MODE and MODE_M300_NAVI_SDK_CTRL

[peterbarker]

LGTM, thanks!

[hamishwillee]

Great, feel free to merge too - I don't have rights here :-)

[hamishwillee]

Fixed the broken enums in AVSSUAS in mavlink/mavlink@20626df

[hamishwillee]

Thanks very much for merging.

[peterbarker]

On Wed, 23 Mar 2022, Hamish Willee wrote: Great, feel free to merge too - I don't have rights here :-)

I was wondering whether this might break CI on the mavlink header generation if the XML fails validation....