Remove redundant \ escape in a literal-style block

[andrewcarver]

I'm not sure how formatting is done in a man page -- I've written exactly zero of them. However, I'm guessing that the literal styling this AsciiDoc source is shown in, makes that \ escape of the copyright symbol-code redundant.

[mojavelinux]

This was actually intentional, though more like a habit. A lot of existing man pages use the literal (C) instead of ©. However, there are also man pages that use ©. To avoid confusion, we'll just go ahead and let it get interpreted in this example.