soc/intel/adl: Add config option to enable FSP-S SATA test mode

For further info on SATA test mode, please refer to this doc:
https://www.intel.com/content/dam/www/public/us/en/documents/white-papers/sata-mqst-setup-paper.pdf

Signed-off-by: Lean Sheng Tan <sheng.tan@9elements.com>
Change-Id: I6ef79fc5723348d5fd10b2ac0847191fa4f37f41
Reviewed-on: https://review.coreboot.org/c/coreboot/+/67410
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
diff --git a/src/soc/intel/alderlake/Kconfig b/src/soc/intel/alderlake/Kconfig
index c79eb08..a73657e 100644
--- a/src/soc/intel/alderlake/Kconfig
+++ b/src/soc/intel/alderlake/Kconfig
@@ -317,6 +317,12 @@
 	help
 	  Select if using S3 instead of S0ix to disable D3Cold.
 
+config ENABLE_SATA_TEST_MODE
+	bool "Enable test mode for SATA margining"
+	default n
+	help
+	  Enable SATA test mode in FSP-S.
+
 config SOC_INTEL_UART_DEV_MAX
 	int
 	default 7