test: use a multiarch capable dpkg rather than workaround

The tests require nowadays a (somewhat) multiarch-capable dpkg, so
replace the workaround as marked in the FIXME with a proper install as
the workaround isn't working always correctly, letting the test fail.

Git-Dch: Ignore

test/integration/test-ubuntu-bug-859188-multiarch-reinstall

@@ -8,14 +8,13 @@ configarchitecture 'amd64' 'i386' 'armel'
 
 buildsimplenativepackage 'libsame' 'amd64,i386,armel' '1.0' 'unstable' 'Multi-Arch: same'
 
-# FIXME: hack around dpkg's current inability to handle multiarch, a clean install would be better…
-insertinstalledpackage 'libsame' 'amd64,i386' '1.0' 'Multi-Arch: same'
-sed -e 's#/installed#/unstable#' -e 's#Installed-Size: 42#Installed-Size: 1#' -i rootdir/var/lib/dpkg/status
-
 setupaptarchive
 
+testsuccess aptget install libsame libsame:i386
+
 REINSTALL='Reading package lists...
 Building dependency tree...
+Reading state information...
 0 upgraded, 0 newly installed, 2 reinstalled, 0 to remove and 0 not upgraded.
 Inst libsame [1.0] (1.0 unstable [amd64])
 Inst libsame:i386 [1.0] (1.0 unstable [i386])