[PATCH] tpm: fix error handling

- handle sysfs error
- handle driver model errors
- de-obfuscate platform_device_register_simple() call, which included an
  assignment in between two function calls, in the same C statement.

Signed-off-by: Jeff Garzik <jeff@garzik.org>
Acked-by: Kylene Hall <kjhall@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>