do not upper case @sc argument in HTML cross manual Cross References

[Patrice Dumas]

Hello,

Right now, as seen in "HTML Cross-reference Command Expansion"

 For @sc, any letters are capitalized.

I'd like to change that for 3 reasons
* what capitalization means could differ for locales
* how this capitalization applies to @sc arguments is not well defined
* it adds unnecessary complexity and ambiguity

What do you think?

The cross-manual references involving @sc will be broken until the
manuals linking to or from are regenerated.  But this should not concern
very few manuals, if any.

-- 
Pat