[gentoo-doc] Xorg Documentation Suggestion

[Roger A. Simoneau]

Greetings;

I've been in the process of upgrading (been a couple years).  I ran into
a bit of an issue that took a bit to resolve.  My suggestion comes based
on what I did to resolve the issue.

Please add a reference to the X Server Configuration Howto that the
individual may require emerging xf86-input-evdev prior to execution of
the X server.  In my case, that package wasn't automatically emerged
when I emerged the Xorg server.

Thanks!
Roger S.