tpm: rework tpm_get_timeouts()

IRQ probing needs to know that the TPM is working before trying to
probe, so move tpm_get_timeouts() to the top of the tpm_tis_init().
This has the advantage of also getting the correct timeouts loaded
before doing IRQ probing.

All the timeout handling code is moved to tpm_get_timeouts() in order to
remove duplicate code in tpm_tis and tpm_crb.

[jarkko.sakkinen@linux.intel.com: squashed two patches together and
improved the commit message.]

Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Tested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Tested-by: Martin Wilck <Martin.Wilck@ts.fujitsu.com>
Tested-by: Scot Doyle <lkml14@scotdoyle.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Acked-by: Peter Huewe <peterhuewe@gmx.de>