If there is a failure before the tb_switch_add() is called the switch
object is released by tb_switch_release() but at that point HopID IDAs
have not yet been initialized. So we see splat like this:

BUG: spinlock bad magic on CPU#2, kworker/u8:5/115
...
Workqueue: thunderbolt0 tb_handle_hotplug
Call Trace:
 dump_stack+0x97/0xdc
 ? spin_bug+0x9a/0xa7
 do_raw_spin_lock+0x68/0x98
 _raw_spin_lock_irqsave+0x3f/0x5d
 ida_destroy+0x4f/0x127
 tb_switch_release+0x6d/0xfd
 device_release+0x2c/0x7d
 kobject_put+0x9b/0xbc
 tb_handle_hotplug+0x278/0x452
 process_one_work+0x1db/0x396
 worker_thread+0x216/0x375
 kthread+0x14d/0x155
 ? pr_cont_work+0x58/0x58
 ? kthread_blkcg+0x2e/0x2e
 ret_from_fork+0x1f/0x40

Fix this by always initializing HopID IDAs in tb_switch_alloc().

Fixes: 0b2863ac ("thunderbolt: Add functions for allocating and releasing HopIDs")
Cc: stable@vger.kernel.org
Reported-by: Chiranjeevi Rapolu <chiranjeevi.rapolu@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>