ports/148096: archivers/xz: packages linux_base-* can not be built from ports on amd64

[naddy at FreeBSD.org]

Synopsis: archivers/xz: packages linux_base-* can not be built from ports on amd64

Responsible-Changed-From-To: naddy->freebsd-emulation
Responsible-Changed-By: naddy
Responsible-Changed-When: Sun Jul 11 16:36:06 UTC 2010
Responsible-Changed-Why: 
This is indeed a problem with emulators/linux_base-*.  These ports
set ARCH=i386 on amd64.  This value of ARCH is then passed on
recursively when a dependency is installed, which then uses
CONFIGURE_TARGET=i386-portbld-freebsd${OSREL}, causing problems on
amd64.

http://www.freebsd.org/cgi/query-pr.cgi?pr=148096