If we discover the TIS TPM device via PNP, use the PNP IRQ information rather
than probing for an IRQ.  If PNP shows no IRQ, run the TPM in polling mode.

Tested-by: <valdis.kletnieks@vt.edu>
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Kylene Hall <kjhall@us.ibm.com>
Cc: <tpm@selhorst.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>