soc/intel/alderlake/iomap: Fix the PCR BAR size on ADL-S

According to ADL PCH BIOS specification (DOC# 630603) ADL-S PCH
uses a fixed SBREG_BAR of 256MiB starting at 0xe0000000.

Signed-off-by: Michał Żygowski <michal.zygowski@3mdeb.com>
Change-Id: Ied59a6dad8fb065dc3aeb6281bd32074aaa5e3b8
Reviewed-on: https://review.coreboot.org/c/coreboot/+/69948
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Eric Lai <eric_lai@quanta.corp-partner.google.com>

src/soc/intel/alderlake/include/soc/iomap.h

@@ -123,6 +123,10 @@
 #define TCO_BASE_SIZE		0x20
 
 #define P2SB_BAR		CONFIG_PCR_BASE_ADDRESS
+#if CONFIG(SOC_INTEL_ALDERLAKE_PCH_S)
+#define P2SB_SIZE		(256 * MiB)
+#else
 #define P2SB_SIZE		(16 * MiB)
+#endif
 
 #endif