"postinstall-fix-obsolete_stand" doesn't remove pae, xen modules on i386, amd64

["John D. Baker" <jdbaker%mylinuxisp.com@localhost>]

Some time ago, the "postinstall-fix-obsolete_stand" phase was added to
automatically remove stale kernel modules for update builds when the
version changed.

At some point before the netbsd-7 branch, i386 and amd64 began building
additional modules to support modular XEN kernels (and modular XEN kernels
with PAE on i386).

Unfortunately the "./stand/i386{,pae}-xen/7.99.1/modules/*" and
"./stand/amd64-xen/7.99.1/modules/*" paths are not removed, causing
"checkflist" to complain about files in DESTDIR not in flist.

-- 
|/"\ John D. Baker, KN5UKS               NetBSD     Darwin/MacOS X
|\ / jdbaker[snail]mylinuxisp[flyspeck]com    OpenBSD            FreeBSD
| X  No HTML/proprietary data in email.   BSD just sits there and works!
|/ \ GPGkeyID:  D703 4A7E 479F 63F8 D3F4  BD99 9572 8F23 E4AD 1645