soc/intel/meteorlake: Provide access to IOE through P2SB SBI for TCSS

soc/intel/meteorlake: Provide access to IOE through P2SB SBI for TCSS

This change provides access to IOE through P2SB Sideband interface for
Meteor Lake TCSS functions of pad configuration and Thunderbolt
authentication. There is a policy of locking the P2SB access at the end
of platform initialization. The tbt_authentication is read from IOM
register through IOE P2SB at early silicon initialization phase and its
usage is deferred to usb4 driver.

BUG=b:213574324
TEST=Built coreboot and validated booting to OS successfully on MTLRVP
board. No boot hung was observed.

Change-Id: Icd644c945bd293a8b9c4a364aaed99ec4a7c12f9
Signed-off-by: John Zhao <john.zhao@intel.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/66410
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Subrata Banik <subratabanik@google.com>
Reviewed-by: Tarun Tuli <taruntuli@google.com>