cb/kabylake: don't hardcode power_on_after_fail

I realised that the Dell OptiPlex 3050 Micro has NVRAM available.
Use that backend, and hardcode power_on_after_fail to Disable,
which is already done in cmos.default.

The Lenovo ThinkPad T480 currently has no option table in coreboot,
besides the CBFS one. For this, the CBFS option table has been
enabled, and the build system has been modified to insert
a relevant config for power_on_after_fail.

Nicholas Chin informs me that Kabylake generally has legacy NVRAM,
so enabling it for the T480/T480s should work, but we'll need
to use it in the future anyway; better to just use CBFS now.

I *could* use the CBFS backend on 3050micro as well.

Signed-off-by: Leah Rowe <leah@libreboot.org>

config/coreboot/default/patches/0030-soc-intel-skylake-configure-usb-acpi.patch

@@ -1,7 +1,7 @@
-From c58079787f45fd9d42bfaedfcb540634787c3010 Mon Sep 17 00:00:00 2001
+From 819fe0e89e426d3d875cf8ab4d2de439ba716848 Mon Sep 17 00:00:00 2001
 From: Felix Singer <felixsinger@posteo.net>
 Date: Wed, 26 Jun 2024 04:24:31 +0200
-Subject: [PATCH 30/35] soc/intel/skylake: configure usb acpi
+Subject: [PATCH 30/40] soc/intel/skylake: configure usb acpi
 
 Change-Id: I53fc73046e4b107064fa8c3c617ba6d9b807b71d
 Signed-off-by: Felix Singer <felixsinger@posteo.net>
@@ -90,5 +90,5 @@ index 6538a1475b..dfb81d496e 100644
  		device pci 14.2 alias thermal      off                     end
  		device pci 14.3 alias cio          off                     end
 -- 
-2.39.5
+2.47.3