Bug#365282: Fix for preinst bug

[Steven Brown <swbrown@variadic.org>]

This bug was due to some debconf migration code in config trying to 
access the xserver-xorg/config/inputdevice/mouse/zaxismapping template 
which might not exist (at least, I don't have it).  Should be safe to 
just ignore.  Patch to config is attached.
Fix bug in xserver-xorg 1:7.0.15 package's config affecting preinst due to
xserver-xorg/config/inputdevice/mouse/zaxismapping not necessarily existing.

- Steven Brown <swbrown@variadic.org>


--- xserver-xorg.config.in	2006-04-27 21:18:58.000000000 -0700
+++ xserver-xorg.config.in-fixed	2006-04-28 22:03:13.000000000 -0700
@@ -457,7 +457,8 @@
   fi
 fi
 
-# migrate from old select-type templates
+# migrate from old select-type templates, if they exist
+set +e
 for TEMPLATE in xserver-xorg/config/inputdevice/mouse/emulate3buttons \
                 xserver-xorg/config/inputdevice/mouse/zaxismapping; do
   db_get "$TEMPLATE"
@@ -467,6 +468,7 @@
     db_set $TEMPLATE "false"
   fi
 done
+set -e
 
 # migrate from "expert" to "advanced"
 db_get xserver-xorg/config/monitor/selection-method