pkg/37680: pkg_add -uu deinstalls a package before checking whether the new version can be installed

[rillig%NetBSD.org@localhost]

>Number:         37680
>Category:       pkg
>Synopsis:       pkg_add -uu deinstalls a package before checking whether the 
>new version can be installed
>Confidential:   no
>Severity:       critical
>Priority:       high
>Responsible:    pkg-manager
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Jan 03 13:55:00 +0000 2008
>Originator:     Roland Illig
>Release:        pkgsrc-current
>Organization:
>Environment:
>Description:

>How-To-Repeat:
$ pkg_info -e "kdeacc*"
kdeaccessibility-3.5.8

$ pkg_add -uu kdeaccessibility-3.5.8nb1
pkg_add: Attempting to update `kdebase>=3.5.8nb2' using binary package

pkg_add: no pkg found for 'kdebase>=3.5.8nb2.tgz', sorry.
pkg_add: 1 package addition failed
pkg_add: autoload of dependency `kdebase>=3.5.8nb2.tgz' failed!
pkg_add: pkg `kdebase>=3.5.8nb2' required, but `kdebase-3.5.8' found installed.
pkg_add: Attempting to update `kdelibs>=3.5.8nb2' using binary package

pkg_add: no pkg found for 'kdelibs>=3.5.8nb2.tgz', sorry.
pkg_add: 1 package addition failed
pkg_add: autoload of dependency `kdelibs>=3.5.8nb2.tgz' failed!
pkg_add: pkg `kdelibs>=3.5.8nb2' required, but `kdelibs-3.5.8' found installed.
pkg_add: Please resolve this conflict!
pkg_add: renaming "/usr/pkg/var/db/pkg/.kdeaccessibility-3.5.8.+REQUIRED_BY" to 
"/usr/pkg/var/db/pkg/kdeaccessibility-3.5.8nb1/+REQUIRED_BY" failed: No such 
file or directory

$ pkg_info -e "kdeacc*"
# nothing

>Fix: