soc/mediatek/common: Move SPM_SYSTEM_BASE_OFFSET to soc folders

MT8196's SPM_SYSTEM_BASE_OFFSET has a different offset due to the
hardware design. To avoid adding a new kconfig for differentiation,
migrate this definition into SoC specific value.

BUG=none
TEST=emerge-geralt coreboot && emerge-corsola coreboot

Change-Id: I5df510d5d05a0594d87e7e96e1e03e20a018785f
Signed-off-by: Yidi Lin <yidilin@chromium.org>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/85625
Reviewed-by: Yu-Ping Wu <yupingso@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/soc/mediatek/common/include/soc/spm_common.h

@@ -5,8 +5,6 @@
 
 #include <soc/mcu_common.h>
 
-#define SPM_SYSTEM_BASE_OFFSET	0x40000000
-
 struct pcm_desc {
 	u32 pmem_words;
 	u32 total_words;

src/soc/mediatek/mt8186/include/soc/spm.h

@@ -14,6 +14,7 @@
 #include <soc/spm_common.h>
 #include <types.h>
 
+#define SPM_SYSTEM_BASE_OFFSET		0x40000000
 #define SPM_INIT_DONE_US		20
 
 #define CLK_SCP_CFG_0			(IO_PHYS + 0x200)

src/soc/mediatek/mt8188/include/soc/spm.h

@@ -9,6 +9,8 @@
 #include <soc/spm_common.h>
 #include <types.h>
 
+#define SPM_SYSTEM_BASE_OFFSET	0x40000000
+
 /* SPM READ/WRITE CFG */
 #define SPM_PROJECT_CODE			0xb16
 #define SPM_REGWR_CFG_KEY			(SPM_PROJECT_CODE << 16)

src/soc/mediatek/mt8192/include/soc/spm.h

@@ -9,6 +9,8 @@
 #include <soc/spm_common.h>
 #include <types.h>
 
+#define SPM_SYSTEM_BASE_OFFSET	0x40000000
+
 /* SPM READ/WRITE CFG */
 #define SPM_PROJECT_CODE                    0xb16
 #define SPM_REGWR_CFG_KEY                   (SPM_PROJECT_CODE << 16)

src/soc/mediatek/mt8195/include/soc/spm.h

@@ -9,6 +9,8 @@
 #include <soc/spm_common.h>
 #include <types.h>
 
+#define SPM_SYSTEM_BASE_OFFSET	0x40000000
+
 /* SPM READ/WRITE CFG */
 #define SPM_PROJECT_CODE			0xb16
 #define SPM_REGWR_CFG_KEY			(SPM_PROJECT_CODE << 16)