tpm: tpm_tis: Fix compile problems with CONFIG_PM_SLEEP/CONFIG_PNP

If CONFIG_PM_SLEEP=n, CONFIG_PNP=y we get this warning:

drivers/char/tpm/tpm_tis.c:706:13: warning: 'tpm_tis_reenable_interrupts' defined but not used [-Wunused-function]

This seems to have been introduced in a2fa3fb0 'tpm: convert tpm_tis driver
to use dev_pm_ops from legacy pm_ops'

Also, unpon reviewing, the #ifdefs around tpm_tis_pm are not right, the first
reference is protected, the second is not. tpm_tis_pm is always defined so we
can drop the #ifdef.

Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Signed-off-by: Peter Huewe <peterhuewe@gmx.de>