hw/misc/mps2-scc: Fix condition for CFG3 register

hw/misc/mps2-scc: Fix condition for CFG3 register

We currently guard the CFG3 register read with
 (scc_partno(s) == 0x524 && scc_partno(s) == 0x547)
which is clearly wrong as it is never true.

This register is present on all board types except AN524
and AN527; correct the condition.

Fixes: 6ac80818941829c0 ("hw/misc/mps2-scc: Implement changes for AN547")
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20240206132931.38376-6-peter.maydell@linaro.org