sb/amd/pi/hudson: Fix UART address math
Correct a build error that occurs when HUDSON_UART is selected.
Replace sizeof() of a nonexistent variable with the intended type.
This was introduced in
bd48b23 "southbridge//hudson: Get rid of void pointer math".
BUG=b:
118484178
TEST=Build Bettong with Chipset/"UART controller for Kern"
Change-Id: Icc0ff9d80c3f5cab9ab837cf1cd0cd8eb0753284
Signed-off-by: Marshall Dawson <marshalldawson3rd@gmail.com>
Reviewed-on: https://review.coreboot.org/c/30072
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Martin Roth <martinroth@google.com>