char: tpm: cr50: Set TPM_FIRMWARE_POWER_MANAGED based on device property

Set TPM_FIRMWARE_POWER_MANAGED flag based on 'firmware-power-managed'
ACPI DSD property. For the CR50 TPM, this flag defaults to true when
the property is unset.

When this flag is set to false, the CR50 TPM driver will always send
a shutdown command whenever the system suspends.

Signed-off-by: Rob Barnes <robbarnes@google.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>