mb/google/brya/var/xol: Add storage option in FW_CONFIG

Add STORAGE config in FW_CONFIG to support NVME sku.

- STORAGE_UFS : 0
- STORAGE_NVME: 1

BUG=b:326481458
BRANCH=firmware-brya-14505.B
TEST=FW_NAME=xol emerge-brya coreboot chromeos-bootimage

Change-Id: Id8316f643ba9a55319b67431a24a507e92419aa7
Signed-off-by: Seunghwan Kim <sh_.kim@samsung.corp-partner.google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/80767
Reviewed-by: Kapil Porwal <kapilporwal@google.com>
Reviewed-by: Eric Lai <ericllai@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Subrata Banik <subratabanik@google.com>

src/mainboard/google/brya/variants/xol/overridetree.cb

@@ -1,3 +1,9 @@
+fw_config
+	field STORAGE 0 0
+		option STORAGE_UFS			0
+		option STORAGE_NVME			1
+	end
+end
 
 chip soc/intel/alderlake
 	register "domain_vr_config[VR_DOMAIN_IA]" = "{
@@ -261,7 +267,8 @@ chip soc/intel/alderlake
 				.clk_src = 1,
 				.flags = PCIE_RP_LTR | PCIE_RP_AER,
 			}"
-		end # SSD
+			probe STORAGE STORAGE_NVME
+		end # NVMe
 		device ref tbt_pcie_rp0 off end
 		device ref tbt_pcie_rp1 off end
 		device ref tbt_pcie_rp2 off end
@@ -273,8 +280,11 @@ chip soc/intel/alderlake
 				register "add_acpi_dma_property" = "true"
 				device generic 0 on end
 			end
+			probe STORAGE STORAGE_UFS
+		end
+		device ref ufs on
+			probe STORAGE STORAGE_UFS
 		end
-		device ref ufs on end
 		device ref cnvi_wifi on
 			chip drivers/wifi/generic
 				register "wake" = "GPE0_PME_B0"