mb/system76/adl-p: galp6: Disable SATA

galp6 only has one SSD slot connected to the CPU, which doesn't support
SATA.

Change-Id: If42b4b0c8d47d2205e1784bed98e45159ede6b8a
Signed-off-by: Tim Crawford <tcrawford@system76.com>

Author: crawfxrd

src/mainboard/system76/adl-p/variants/galp6/overridetree.cb

@@ -129,6 +129,7 @@ chip soc/intel/alderlake
 				device i2c 38 on end
 			end
 		end
+		device ref sata off end
 		device ref pcie_rp5 on
 			# PCIe RP#5 x1, Clock 2 (WLAN)
 			register "pch_pcie_rp[PCH_RP(5)]" = "{