acer/aspire_vn7_572g: Drop superfluous SATA AHCI mode configuration

The SATA controller is configured to AHCI mode by default. Drop the
setting from the devicetree.

Change-Id: I027b393300e2cbad827e176afddc197007314f10
Signed-off-by: Felix Singer <felixsinger@posteo.net>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/83178
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-by: Marvin Evers <marvin.n.evers@gmail.com>

src/mainboard/acer/aspire_vn7_572g/devicetree.cb

@@ -243,7 +243,6 @@ chip soc/intel/skylake
 		end
 		device ref heci1	on	end
 		device ref sata		on
-			register "SataMode" = "SATA_AHCI"
 			register "SataSalpSupport" = "1"
 			register "SataPortsEnable[1]" = "1"	# HDD; BIT1 in 92h-93h
 			register "SataPortsEnable[2]" = "1"	# ODD; BIT2 in 92h-93h