powerpc/pseries: Release DRC when configure_connector fails

Commit f32393c943e2 ("powerpc/pseries: Correct cpu affinity for
dlpar added cpus") moved dlpar_acquire_drc() call to before
dlpar_configure_connector() call in dlpar_cpu_probe(), but missed
to release the DRC if dlpar_configure_connector() failed.
During CPU hotplug, if configure-connector fails for any reason,
then this will result in subsequent CPU hotplug attempts to fail.

Release the acquired DRC if dlpar_configure_connector() call fails
so that the DRC is left in right isolation and allocation state
for the subsequent hotplug operation to succeed.

Fixes: f32393c943e2 ("powerpc/pseries: Correct cpu affinity for dlpar added cpus")
Cc: [e-mail] # 4.1+
Signed-off-by: Bharata B Rao <[e-mail]>
Reviewed-by: Nathan Fontenot <[e-mail]>
Signed-off-by: Michael Ellerman <[e-mail]>

arch/powerpc/platforms/pseries/dlpar.c

···
 
 	dn = dlpar_configure_connector(cpu_to_be32(drc_index), parent);
 	of_node_put(parent);
-	if (!dn)
+	if (!dn) {
+		dlpar_release_drc(drc_index);
 		return -EINVAL;
+	}
 
 	rc = dlpar_attach_node(dn);
 	if (rc) {