ipmi: proper spinlock initialization

Unloading ipmi module can trigger following error.  (if
CONFIG_DEBUG_SPINLOCK=y)

[ 9633.779590] BUG: spinlock bad magic on CPU#1, rmmod/7170
[ 9633.779606]  lock: f41f5414, .magic: 00000000, .owner:
<none>/-1, .owner_cpu: 0
[ 9633.779626] Pid: 7170, comm: rmmod Not tainted
2.6.36-rc7-11474-gb71eb1e-dirty #328
[ 9633.779644] Call Trace:
[ 9633.779657]  [<c13921cc>] ? printk+0x18/0x1c
[ 9633.779672]  [<c11a1f33>] spin_bug+0xa3/0xf0
[ 9633.779685]  [<c11a1ffd>] do_raw_spin_lock+0x7d/0x160
[ 9633.779702]  [<c1131537>] ? release_sysfs_dirent+0x47/0xb0
[ 9633.779718]  [<c1131b78>] ? sysfs_addrm_finish+0xa8/0xd0
[ 9633.779734]  [<c1394bac>] _raw_spin_lock_irqsave+0xc/0x20
[ 9633.779752]  [<f99d93da>] cleanup_one_si+0x6a/0x200 [ipmi_si]
[ 9633.779768]  [<c11305b2>] ? sysfs_hash_and_remove+0x72/0x80
[ 9633.779786]  [<f99dcf26>] ipmi_pnp_remove+0xd/0xf [ipmi_si]
[ 9633.779802]  [<c11f622b>] pnp_device_remove+0x1b/0x40

Fix this by initializing spinlocks in a smi_info_alloc() helper function,
right after memory allocation and clearing.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: David Miller <davem@davemloft.net>
Cc: Yinghai Lu <yinghai@kernel.org>
Acked-by: Corey Minyard <cminyard@mvista.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>