arch/x86/acpi: Allow "transparent" ACPI device names

Certain devices, such as the northbridge on AMD Opteron systems,
do not require a node in the ACPI device path.  Allow such devices
to be passed over by the ACPI path generator if the device-specific
ACPI name function returns a zero-length (non-NULL) string.

Change-Id: Iffffc9a30b395b0bd6d60e411439a437e89f554e
Signed-off-by: Timothy Pearson <tpearson@raptorengineering.com>
Reviewed-on: https://review.coreboot.org/19281
Tested-by: build bot (Jenkins)
Tested-by: Raptor Engineering Automated Test Stand <noreply@raptorengineeringinc.com>
Reviewed-by: Duncan Laurie <dlaurie@chromium.org>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
1 file changed