arch/x86: Write ACPI DBG2 table only if the device has been enabled

The commit 93bbd41e (soc/intel: Enable ACPI DBG2 table generation)
causes a crash on the mainboard mc_apl1. On this mainboard all internal
SOC UARTs in the devicetree are switched off. As a result, no resources
are allocated to the UARTs. The function find_resource() expects an
existing resource. Otherwise, the CPU will stop. It should therefore not
only be queried whether a device is present, but also whether it is
enabled.

Change-Id: I56ce44ae0cf77916fcb640f79fb8944fe33177cd
Signed-off-by: Mario Scheithauer <mario.scheithauer@siemens.com>
Reviewed-on: https://review.coreboot.org/22552
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-by: Duncan Laurie <dlaurie@chromium.org>
1 file changed