torture: make kvm-find-errors.sh check for compressed vmlinux files

Under some conditions, a given run's vmlinux file will be compressed,
so that it is named vmlinux.xz rather than vmlinux.  in such cases,
kvm-find-errors.sh will complain about the nonexistence of vmlinux.
This commit therefore causes kvm-find-errors.sh to check for vmlinux.xz
as well as for vmlinux.

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

Author: paulmckrcu

tools/testing/selftests/rcutorture/bin/kvm-find-errors.sh

@@ -36,7 +36,7 @@ do
 	then
 		egrep "error:|warning:|^ld: .*undefined reference to" < $i > $i.diags
 		files="$files $i.diags $i"
-	elif ! test -f ${scenariobasedir}/vmlinux && ! test -f "${rundir}/re-run"
+	elif ! test -f ${scenariobasedir}/vmlinux && ! test -f ${scenariobasedir}/vmlinux.xz && ! test -f "${rundir}/re-run"
 	then
 		echo No ${scenariobasedir}/vmlinux file > $i.diags
 		files="$files $i.diags $i"