i2c: xgene-slimpro: Migrate to use generic PCC shmem related macros

commit 89a4ad1f upstream.

Use the newly defined common and generic PCC shared memory region
related macros in this driver to replace the locally defined ones.

Reviewed-by: Andi Shyti <andi.shyti@kernel.org>
Acked-by: Wolfram Sang <wsa@kernel.org>
Link: https://lore.kernel.org/r/20230927-pcc_defines-v2-2-0b8ffeaef2e5@arm.com


Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Stable-dep-of: 7f9e19f2 ("mailbox: pcc: Check before sending MCTP PCC response ACK")
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>