mb/skyrim/var/frostflow: enable dptc tablet mode switch

add dptc power parameter for tablet mode

sustained_power_limit_mW_tablet : 12w

BUG=b:257187831
BRANCH=none
TEST= validate the parameter changes for each mode by AGT

Signed-off-by: Chris.Wang <chris.wang@amd.corp-partner.google.com>
Change-Id: I22d3f9c79a1eaaccfbef3766019516edb3523964
Reviewed-on: https://review.coreboot.org/c/coreboot/+/70674
Reviewed-by: Frank Wu <frank_wu@compal.corp-partner.google.com>
Reviewed-by: Dtrain Hsu <dtrain_hsu@compal.corp-partner.google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: John Su <john_su@compal.corp-partner.google.com>

src/mainboard/google/skyrim/Kconfig.name

@@ -19,8 +19,9 @@ config BOARD_GOOGLE_MORTHAL
 config BOARD_GOOGLE_FROSTFLOW
 	bool "->  Frostflow"
 	select BOARD_GOOGLE_BASEBOARD_SKYRIM
-	select SOC_AMD_COMMON_BLOCK_ACPI_DPTC
 	select DRIVERS_GENESYSLOGIC_GL9755
+	select FEATURE_TABLET_MODE_DPTC
+	select SOC_AMD_COMMON_BLOCK_ACPI_DPTC
 
 config BOARD_GOOGLE_CRYSTALDRIFT
 	bool "->  Crystaldrift"

src/mainboard/google/skyrim/variants/frostflow/overridetree.cb

@@ -14,6 +14,9 @@ chip soc/amd/mendocino
 	# Set Package Power Parameters
 	register "stapm_time_constant_s" = "200"
 
+	# Power table for tablet mode
+	register "sustained_power_limit_mW_tablet" = "12000"
+
 	register "i2c[0]" = "{
 		.speed = I2C_SPEED_FAST,
 		.speed_config[0] = {