PCI: rpaphp: kmalloc/kfree slot->name directly

rpaphp tends to use slot->name directly everywhere, and doesn't
ever need slot->hotplug_slot->name.

struct hotplug_slot->name is going away, so convert rpaphp directly
manipulate its own slot->name everywhere, and don't bother touching
slot->hotplug_slot->name.

Acked-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>