tpm: Make tcpci_pm_ops variable static const

tpm: Make tcpci_pm_ops variable static const

File-scope 'tcpci_pm_ops' is not used outside of this unit and is not
modified anywhere, so make it static const to silence sparse warning:

  tcpci.c:1002:1: warning: symbol 'tcpci_pm_ops' was not declared. Should it be static?

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>