powerpc/pseries: Report DLPAR capabilities

As we add the ability to do DLPAR of additional devices through
the sysfs interface we need to know which devices are supported.
This adds the reporting of supported devices with a comma separated
list reported in the existing /sys/kernel/dlpar.

Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/platforms/pseries/dlpar.c

@@ -551,7 +551,13 @@ dlpar_store_out:
 	return rc ? rc : count;
 }
 
-static CLASS_ATTR(dlpar, S_IWUSR, NULL, dlpar_store);
+static ssize_t dlpar_show(struct class *class, struct class_attribute *attr,
+			  char *buf)
+{
+	return sprintf(buf, "%s\n", "memory,cpu");
+}
+
+static CLASS_ATTR(dlpar, S_IWUSR | S_IRUSR, dlpar_show, dlpar_store);
 
 static int __init pseries_dlpar_init(void)
 {