pkg/38714: x11-links should set suitable PKG_FAIL_REASON if reached from modular-xorg-*

[dholland%netbsd.org@localhost]

>Number:         38714
>Category:       pkg
>Synopsis:       x11-links should set suitable PKG_FAIL_REASON if reached from 
>modular-xorg-*
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    pkg-manager
>State:          open
>Class:          change-request
>Submitter-Id:   net
>Arrival-Date:   Wed May 21 04:00:04 +0000 2008
>Originator:     David A. Holland
>Release:        pkgsrc of 20080520
>Organization:
>Environment:
irrelevant
>Description:

Trying to build modular-xorg-libs while X11_TYPE is still set to
"native" reaches x11-links; this fails, and says it's failing because
X headers aren't installed.

This looks like a circular dependency and is consequently confusing.

(Seen on chat.)

>How-To-Repeat:

make on a machine with no X installed and without X11_TYPE set properly.

>Fix:

add a X11_TYPE_REQUIRED variable to the appropriate packages and test
in in the x11 buildlink stuff, setting PKG_FAIL_REASON to something
like "This package requires X11_TYPE=modular (currently ${X11_TYPE})"

This would also prevent people from trying to install x11-links with
X.org. (Although I'm not sure what happens currently if you do that.)