bug#6523: 24.0.50; Typo in nxml-mode.texi

[Juri Linkov]

> Unfortunately, I've committed your change without a commit log message
> and the relevant --author info because of a C-c C-c that happened too
> soon :-(

I'm often afraid of typing `C-c C-c' too soon when typing `C-c C-a' or
`C-c C-d' it's too easy to mistakenly type `C-c' twice.  Maybe `C-c C-c'
should ask for confirmation?

-- 
Juri Linkov
http://www.jurta.org/emacs/