sb/intel/i82801jx: Add common code for LPC decode

Change-Id: Id706da33f06ceeec39ea50301130770226f0474e
Signed-off-by: Arthur Heymans <arthur@aheymans.xyz>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/36701
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: HAOUAS Elyes <ehaouas@noos.fr>
Reviewed-by: Nico Huber <nico.h@gmx.de>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
diff --git a/src/mainboard/asus/p5qc/variants/p5q_pro/devicetree.cb b/src/mainboard/asus/p5qc/variants/p5q_pro/devicetree.cb
index 6e0a40a..fb818ff 100644
--- a/src/mainboard/asus/p5qc/variants/p5q_pro/devicetree.cb
+++ b/src/mainboard/asus/p5qc/variants/p5q_pro/devicetree.cb
@@ -45,6 +45,9 @@
 			# Enable PCIe ports 0,2,3 as slots.
 			register "pcie_slot_implemented"	= "0x31"
 
+			register "gen1_dec" = "0x00000295"
+			register "gen2_dec" = "0x001c4701"
+
 			device pci 19.0 off end		# GBE
 			device pci 1a.0 on end		# USB
 			device pci 1a.1 on end		# USB